expectancy (n.) Look up expectancy at Dictionary.com
1590s, from Latin expectantia (see expectant) + -ancy.
expectant (adj.) Look up expectant at Dictionary.com
late 14c., from Old French expectant or directly from Latin expectantem/exspectantem (nominative expectans/exspectans), present participle of expectare/exspectare (see expect). Related: Expectantly. As a noun, from 1620s.
expectation (n.) Look up expectation at Dictionary.com
1530s, from Middle French expectation (14c.) or directly from Latin expectationem/exspectationem (nominative expectatio/exspectatio) "anticipation, an awaiting," noun of action from past participle stem of expectare/exspectare (see expect). Related: Expectations.
expectorant (n.) Look up expectorant at Dictionary.com
1782, from Latin expectorantem (nominative expectorans), present participle of expectorare (see expectorate). From 1811 as an adjective.
expectorate (v.) Look up expectorate at Dictionary.com
c.1600, "to clear out the chest or lungs," from Latin expectoratus, past participle of expectorare "scorn, expel from the mind," literally "make a clean breast," from ex- "out" (see ex-) + pectus (genitive pectoris) "breast" (see pectoral (adj.)). Use as a euphemism for "spit" is first recorded 1827. Original sense in expectorant. Related: Expectorated; expectorating.
expectoration (n.) Look up expectoration at Dictionary.com
1670s, noun of action from expectorate.
expediate (v.) Look up expediate at Dictionary.com
a 17c. error for expedite that has gotten into the dictionaries.
expedience (n.) Look up expedience at Dictionary.com
mid-15c., "advantage, benefit," from Old French expedience, from Late Latin expedientia, from expedientem (see expedient). Related: Expediency (1610s).
expedient (adj.) Look up expedient at Dictionary.com
late 14c., "advantageous, fit, proper," from Old French expedient (14c.) or directly from Latin expedientem (nominative expediens) "beneficial," present participle of expedire "make fit or ready, prepare" (see expedite). The noun meaning "a device adopted in an exigency, a resource" is from 1650s. Related: Expediential; expedientially (both 19c.)
expediently (adv.) Look up expediently at Dictionary.com
late 14c., from expedient (adj.) + -ly (2).
expedite (v.) Look up expedite at Dictionary.com
late 15c. (implied in past participle expedit), from Latin expeditus, past participle of expedire "extricate, disengage, liberate; procure, make ready, make fit, prepare," literally "free the feet from fetters," hence "liberate from difficulties," from ex- "out" (see ex-) + *pedis "fetter, chain for the feet," related to pes (genitive pedis) "foot" (see foot (n.)). Compare Greek pede "fetter." Related: Expedited; expediting.
expedition (n.) Look up expedition at Dictionary.com
early 15c., "military campaign; the act of rapidly setting forth," from Middle French expédition (13c.) and directly from Latin expeditionem (nominative expeditio), noun of action from past participle stem of expedire (see expedite). Meaning "journey for some purpose" is from 1590s. Sense by 1690s also included the body of persons on such a journey. Related: Expeditionary.
expeditious (adj.) Look up expeditious at Dictionary.com
late 15c., expedycius "useful, fitting," from Latin expeditus "disengaged, ready, prompt," past participle of expidere (see expedite). Meaning "speedy" is from 1590s. Related: Expeditiously; expeditiousness.
expel (v.) Look up expel at Dictionary.com
late 14c., from Latin expellere "drive out," from ex- "out" (see ex-) + pellere "to drive" (see pulse (n.1)). Meaning "to eject from a school" is first recorded 1640s. Related: Expelled; expelling.
expellee (n.) Look up expellee at Dictionary.com
1888, from expel + -ee.
expend (v.) Look up expend at Dictionary.com
early 15c., from Latin expendere "pay out, weigh out money," from ex- "out" (see ex-) + pendere "to pay, weigh" (see pendant). Related: Expended; expending.
expendable (adj.) Look up expendable at Dictionary.com
1805, from expend + -able.
expenditure (n.) Look up expenditure at Dictionary.com
1769, from Medieval Latin expenditus, irregular past participle of expendere (see expend) + -ure. Related: Expenditures.
expense (n.) Look up expense at Dictionary.com
late 14c., from Anglo-French expense, Old French espense "money provided for expenses," from Late Latin expensa "disbursement, outlay, expense," noun use of neuter plural past participle of Latin expendere "to weigh out money, to pay down" (see expend).

Latin spensa also yielded Medieval Latin spe(n)sa, whose sense specialized to "outlay for provisions," then "provisions, food," which was borrowed into Old High German as spisa and is the root of German Speise "food," now mostly meaning prepared food, and speisen "to eat."
expense (v.) Look up expense at Dictionary.com
1909, from expense (n.). Related: Expensed; expensing.
expenses (n.) Look up expenses at Dictionary.com
"charges incurred in the discharge of duty," late 14c. See expense (n.).
expensive (adj.) Look up expensive at Dictionary.com
1620s, "given to profuse expenditure," from expense (n.) + -ive. Meaning "costly" is from 1630s. Earlier was expenseful (c.1600). Expenseless was in use mid-17c.-18c., but there seems now nothing notable to which it applies, and the dictionaries label it "obsolete."
experience (n.) Look up experience at Dictionary.com
late 14c., "observation as the source of knowledge; actual observation; an event which has affected one," from Old French esperience (13c.) "experiment, proof, experience," from Latin experientia "knowledge gained by repeated trials," from experientem (nominative experiens), present participle of experiri "to try, test," from ex- "out of" (see ex-) + peritus "experienced, tested," from PIE root *per- "to lead, pass over" (see peril). Meaning "state of having done something and gotten handy at it" is from late 15c.
experience (v.) Look up experience at Dictionary.com
1530s, "to test, try;" see experience (n.). Sense of "feel, undergo" first recorded 1580s. Related: Experienced; experiences; experiencing.
experienced (adj.) Look up experienced at Dictionary.com
"having experience; skillful through expereince," 1570s, past participle adjective from experience (v.).
experiential (adj.) Look up experiential at Dictionary.com
1640s (implied in experientially), from Latin experientia (see experience (n.)) + -al (1).
experiment (n.) Look up experiment at Dictionary.com
mid-14c., from Old French esperment "practical knowledge, cunning, enchantment; trial, proof, example, lesson," from Latin experimentum "a trial, test, proof, experiment," noun of action from experiri "to test, try" (see experience (n.)).
experiment (v.) Look up experiment at Dictionary.com
late 15c., from experiment (n.). Related: Experimented; experimenting.
experimental (adj.) Look up experimental at Dictionary.com
mid 15c., "having experience," from experiment (n.) + -al (1). Meaning "based on experience" is from 1560s. Meaning "for the sake of experiment" is from 1792 (as in Experimental farm).
experimentation (n.) Look up experimentation at Dictionary.com
1670s; see experiment (v.) + -ation.
expert (adj.) Look up expert at Dictionary.com
late 14c., from Old French expert and directly from Latin expertus, past participle of experiri "to try, test" (see experience). The noun sense of "person wise through experience" existed 15c., reappeared 1825. Related: Expertly.
expertise (n.) Look up expertise at Dictionary.com
1868, from French expertise (16c.) "expert appraisal, expert's report," from expert (see expert). Earlier in same sense was expertness (c.1600).
experto crede Look up experto crede at Dictionary.com
Latin ("Aeneid," xi.283), "take it from one who knows;" from dative singular of expertus (see expert (adj.)) + imperative singular of credere (see credo).
expiate (v.) Look up expiate at Dictionary.com
c.1600 (OED entry has a typographical error in the earliest date), from Latin expiatus, past participle of expiare "to make amends, atone for" (see expiation). Related: Expiable (1560s); expiated; expiating.
expiation (n.) Look up expiation at Dictionary.com
early 15c., via Middle French expiation or directly from Latin expiationem (nominative expiatio) "satisfaction, atonement," noun of action from past participle stem of expiare "make amends," from ex- "completely" (see ex-) + piare "propitiate, appease," from pius "faithful, loyal, devout" (see pious).
The sacrifice of expiation is that which tendeth to appease the wrath of God. [Thomas Norton, translation of Calvin's "Institutes of Christian Religion," 1561]
expiatory (adj.) Look up expiatory at Dictionary.com
1540s, from Latin expiatorius, from expiat-, past participle stem of expiare (see expiation).
expiration (n.) Look up expiration at Dictionary.com
early 15c., "vapor, breath," from Middle French expiration, from Latin expirationem/exspirationem (nominative expiratio/exspiratio), noun of action from past participle stem of expirare/exspirare (see expire). Meaning "termination, end, close" is from 1560s.
expire (v.) Look up expire at Dictionary.com
c.1400, "to die," from Middle French expirer (12c.) "expire, elapse," from Latin expirare/exspirare "breathe out, breathe one's last, die," from ex- "out" (see ex-) + spirare "to breathe" (see spirit (n.)). "Die" is the older sense in English; that of "breathe out" is first attested 1580s. Of laws, patents, treaties, etc., mid-15c. Related: Expired; expiring.
expiry (n.) Look up expiry at Dictionary.com
"close, termination," 1752, from expire + -y (4). Meaning "dying, death" is from 1790.
explain (v.) Look up explain at Dictionary.com
early 15c., from Latin explanare "to make level, smooth out;" also "to explain, make clear" (see explanation).

Originally explane, spelling altered by influence of plain. Also see plane (v.2). In 17c., occasionally used more literally, of the unfolding of material things: Evelyn has buds that "explain into leaves" ["Sylva, or, A discourse of forest-trees, and the propagation of timber in His Majesties dominions," 1664]. Related: Explained; explaining; explains.
explanation (n.) Look up explanation at Dictionary.com
late 14c., from Latin explanationem (nominative explanatio), noun of action from past participle stem of explanare "to make plain or clear, explain," literally "make level, flatten," from ex- "out" (see ex-) + planus "flat" (see plane (n.1)).
explanatory (adj.) Look up explanatory at Dictionary.com
1610s, from or modeled on Late Latin explanatorius "having to do with an explanation," from Latin explanat-, past participle stem of explanare (see explanation).
expletive (n.) Look up expletive at Dictionary.com
1610s, originally "a word or phrase serving to fill out a sentence or metrical line," from Middle French explétif (15c.) and directly from Late Latin expletivus "serving to fill out," from explet-, past participle stem of Latin explere "fill out," from ex- "out" (see ex-) + plere "to fill" (see pleio-).

Sense of "exclamation," often in the form of a cuss word, first recorded 1815 in Sir Walter Scott, popularized by edited transcripts of Watergate tapes (mid-1970s), in which expletive deleted replaced President Nixon's salty expressions. As an adjective, from 1660s.
expletive (adj.) Look up expletive at Dictionary.com
mid-15c., from Latin expletivus (see expletive (n.)).
explicable (adj.) Look up explicable at Dictionary.com
1550s, from or on model of Latin explicabilis "capable of being unraveled, that may be explained," from explicare (see explicit). Middle English had a verb expliken "explain, interpret" (mid-15c.).
explicate (v.) Look up explicate at Dictionary.com
1530s, from Latin explicatus, past participle of explicare "unfold, unravel, explain" (see explicit). Related: Explicated; explicating.
explication (n.) Look up explication at Dictionary.com
1520s, from Middle French explication, from Latin explicationem (nominative explicatio), noun of action from past participle stem of explicare (see explicit).
explicative (adj.) Look up explicative at Dictionary.com
1640s, "having the function of explaining," from Latin explicativus, from past participle stem of explicare (see explicit). As a noun, from 1775.
explicit (adj.) Look up explicit at Dictionary.com
c.1600, from French explicite, from Latin explicitus "unobstructed," variant past participle of explicare "unfold, unravel, explain," from ex- "out" (see ex-) + plicare "to fold" (see ply (v.1)).

"Explicitus" was written at the end of medieval books, originally short for explicitus est liber "the book is unrolled." As a euphemism for "pornographic" it dates from 1971.
explicitly (adv.) Look up explicitly at Dictionary.com
1630s, from explicit + -ly (2). Opposed to implicitly.