n. A secondary articulatory feature of usually consonants that involves the contraction or rounding of the labia during pronunciation.
the GNU version of the Collaborative International Dictionary of English
n. The modification of an articulation by contraction of the lip opening.
The Century Dictionary and Cyclopedia
n. The act or process of labializing; conversion to a labial.
Word Usage
"To me, *h3 was ultimately born from the era of Indo-Aegean Centralization when the feature of labialization was transferred to the neighbouring consonant, including *h."