ewer n.

1830, "artificial pond in a garden or elsewhere for growing aquatic plants," noun use of neuter of Latin aquarius "pertaining to water" (also, as a noun, "water-carrier"), genitive of aqua "water" (from PIE root *akwa- "water").

The noun aquarium in Latin meant "drinking place for cattle." In English, the meaning "vessel of glass filled with water in which living aquatic animals are kept indoors" is by 1853. The Victorian mania for indoor aquariums began with the book "The Aquarium," published 1854 by English naturalist Philip Henry Gosse. An earlier attempt at a name for "fish tank" was marine vivarium.

*akwā-, Proto-Indo-European root meaning "water."

It forms all or part of: aqua; aqua-; aqua vitae; aqualung; aquamarine; aquanaut; aquarelle; aquarium; Aquarius; aquatic; aquatint; aqueduct; aqueous; aquifer; Aquitaine; eau; Evian; ewer; gouache; island; sewer (n.1) "conduit."

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit ap "water;" Hittite akwanzi "they drink;" Latin aqua "water, the sea, rain;" Lithuanian upė "a river;" Old English ea "river," Gothic ahua "river, waters." But Boutkan (2005) writes that only the Germanic and Latin words are sure, Old Irish ab is perhaps related, and "the rest of the evidence in Pokorny (1959) is uncertain."

c. 1400, seuer, "conduit, trench, or ditch used for drainage" (of surface water or marshland), from Anglo-French sewere (early 14c.), Old North French sewiere "sluice from a pond" (13c.), literally "something that makes water flow." From late 13c. in surnames (Robertus Atte Suor). Also compare Anglo-Latin sewera, suera. These are from a shortened form of Gallo-Roman *exaquaria (source of Old French esseveur), from Latin ex "out" (see ex-) + aquaria, fem. of aquarius "pertaining to water," from aqua "water" (from PIE root *akwa- "water"). For form evolution, compare ewer, from Latin aquarius.

After c. 1600 the sense of "underground channel for wastewater" emerged and predomination, especially "a public drain; a conduit or canal constructed to carry off waste water, etc." Figurative use of this is from 1640s. Sewer rat, the common brown rat when infesting sewers, is from 1861.