hyoplastron

Coined by Thomas Henry Huxley in 1872 as hyo- + plastron. Superseded the earlier hyosternum, a nominalised form of the French adjective hyosternal, coined by Étienne Geoffroy Saint-Hilaire in 1818. The prefix is from Ancient Greek ῡ̔οειδής (hūoeidḗs, “shaped like the letter Υ”), ultimately from ὗ (hû, “the Greek letter upsilon”), reflecting its original description as the sternal attachment of the sternohyoid muscle (whose other attachment is on the hyoid bone).