Spencer (n.) Look up Spencer at Dictionary.com
surname attested from late 13c. (earlier le Despenser, c.1200), literally "one who dispenses or has charge of provisions in a household." Middle English spence meant "larder, pantry," and is short for Old French despense (French dépense) "expense," from despenser "to distribute" (see dispense). Another form of the word is spender, which also has become a surname.

As a type of repeating rifle used in the American Civil War, 1863, named for U.S. gunsmith Christopher Spencer, who, with Luke Wheelock, manufactured them in Boston, Mass.