/ Dictionary / Index S subaqueous: Meaning and Definition of Find definitions for: sub•a•que•ous Pronunciation: (sub-ā'kwē-us, -ak'wē-), [key] — adj. existing or situated under water; underwater. occurring or performed under water. used under water. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: subaqueous (Thesaurus) subaquatic subarachnoid Related Content Daily Word Quiz: pundit Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language