"Dilated" means to become larger or wider, often referring to the expansion of a particular part of the body, such as the pupils in your eyes getting bigger.
To explore the phenomenon further, Kret is testing whether viewing eyes with dilated pupils increases trust in volunteers playing a game. (newscientist.com)
Progesterone also plays a primary role in dilating blood vessels, which can help prevent high blood pressure and other heart - related issues. (womenshealthandfitness.com.au)