Having the form of an arch, or of the Greek letter upsilon [1913 Webster]
Of or pertaining to the bony or cartilaginous arch which supports the tongue. Sometimes applied to the tongue itself. [1913 Webster]

Hyoid arch (Anat.), the arch of cartilaginous or bony segments, which connects the base of the tongue with either side of the skull. -- Hyoid bone (Anat.), the bone in the base of the tongue, the middle part of the hyoid arch.

hyoid, n.

The hyoid bone.

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OXFORD DICTIONARY

hyoid, n. & adj. Anat.
--n. (in full hyoid bone) a U-shaped bone in the neck which supports the tongue.
--adj. of or relating to this.

Etymology

F hyo{iuml}de f. mod.L hyo{iuml}des f. Gk huoeides shaped like the letter upsilon (hu)

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