dilates
di-lates
verb
To make or become wider, larger, or more open, often a body part.
"Her pupils dilate in the dark."
Thesaurus
Synonyms: dilate, distend, enlarge, exposit, elaborate, expatiate, lucubrate, expand, expound, flesh out
Antonyms: abbreviate, abridge, contract, cut, foreshorten, reduce, shorten