aqueous (adj.) Look up aqueous at
"of the nature of or abounding in water," 1640s, from Latin aqua "water" (from PIE root *akwa- "water") on analogy of French aqueux "watery" (16c., which, however, is from Late Latin aquosus "abounding in water"). Or by analogy of Latin terreus "earthy," from terra "earth." Aqueous humor is the original use in English. Related: Aqueousness.