The Collaborative International Dictionary of English v.0.48:
Hyoid \Hy"oid\, a. [Gr. ? fr. the letter [Upsilon] + e'i^dos
form: cf. F. hyo["i]de.]
1. Having the form of an arch, or of the Greek letter upsilon
[[Upsilon]].
[1913 Webster]
2. (Anat.) 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.
[1913 Webster]