Entry 1 sense Webster, 1913 Hyoglossus · Hy·o·glos·sus · IPA /ˌhaɪ.oʊˈɡlɑs.əs/ 01 n. A flat muscle on either side of the tongue, connecting it with the hyoid bone. 1. A flat muscle on either side of the tongue, connecting it with the hyoid bone.(Anat.)