"containing no water," 1809, a modern coinage from Greek an- "not, without" (see an- (1)) + hydor "water" (from PIE root *wed- (1) "water; wet") + -ous. Greek did have anhydros "waterless," used of arid lands or corpses that had not been given proper funeral rites.
angularity
Angus
anhedonia
anhinga
anhungered
anhydrous
ani
anigh
anil
aniline
anima