aqua- Look up aqua- at Dictionary.com
word-forming element meaning "water," from Latin aqua "water; the sea; rain," cognate with Proto-Germanic *akhwo (source of Old English ea "river," Gothic ahua "river, waters," Old Norse Ægir, name of the sea-god, Old English ieg "island"), from PIE root *akwā- "water" (source also of Sanskrit ap "water," Hittite akwanzi "they drink," Lithuanian uppe "a river").