n., pl. -tus·es or hiatus.

1. A gap or interruption in space, time, or continuity; a break: “We are likely to be disconcerted by . . . hiatuses of thought” (Edmund Wilson).
2. Linguistics. A slight pause that occurs when two immediately adjacent vowels in consecutive syllables are pronounced, as in reality and naive.
3. Anatomy. A separation, aperture, fissure, or short passage in an organ or body part.

[Latin hiātus, from past participle of hiāre, to gape.]