faint constellation and 11th zodiac sign, late Old English, from Latin aquarius, literally "water carrier," properly an adjective, "pertaining to water" (see aquarium); a loan-translation of Greek Hydrokhoos "the water-pourer," old Greek name of this constellation.
Aquarians were a former Christian sect that used water instead of wine at the Lord's Supper. Age of Aquarius (1940) is an astrological epoch supposed to have begun in the 1960s, embodying the traits of this sign and characterized by world peace and human brotherhood. The term and the concept probably got a boost in popular use when An Aquarian Exposition was used as the sub-name of the Woodstock Music & Art Fair (1969).
1830, noun use of neuter of Latin aquarius "pertaining to water," as a noun, "water-carrier," genitive of aqua "water" (see aqua-). The word existed in Latin, but there it meant "drinking place for cattle." Originally especially for growing aquatic plants; An earlier attempt at a name for "fish tank" was marine vivarium.
"water pitcher with a wide spout," early 14c., from Anglo-French *ewiere, Old French eviere "water pitcher," parallel form of aiguiere (Modern French aiguière), from fem. of Latin aquarius "of or for water," as a noun, "water-carrier" (see aquarium).
c.1400, "conduit," from Anglo-French sewere, Old North French sewiere "sluice from a pond" (13c.), literally "something that makes water flow," from shortened form of Gallo-Roman *exaquaria (source of Middle French esseveur), from Latin ex- "out" (see ex-) + aquaria, fem. of aquarius "pertaining to water," from aqua "water" (see aqua-).
Specifically of underground channels for wastewater from c.1600; figurative use of this is from 1640s.