Entry 1 sense Webster, 1913 Opalesce · O·pal·esce · IPA /oʊpəˈlɛs/ 01 v. i. To give forth a play of colors, like the opal. imp. & p. p. Opalesced; p. pr. & vb. n. Opalescing 1. To give forth a play of colors, like the opal.