Literally meaning: shaped like the letter υ (hypsilon)
Origin: Anc Greek
υ/hy=u as the letter “u” corresponded to Greek letter «υ» (uppercase Υ, lowercase υ)
the 20th letter of Greek alphabet.
-οειδής/-oides(=-oid, prefix meaning “like”, “type”, “form”)
Upsilon is known as Pythagoras' letter because the Greek philosopher and mathematician (570–c. 495 BC) used it as a symbol of the path of vice.
Hyoid is the U shaped bone at the base of the tongue between the chin and the thyroid which is not directly attached to other bones supporting tongue muscles.