What is the X in X-mas?
1570s, from Late Latin onomatopoeia, from Greek onomatopoiia "the making of a name or word" (in imitation of a sound associated with the thing being named), from onomatopoios, from onoma (genitive onomatos) "word, name" (see name (n.)) + a derivative of poiein "compose, make" (see poet). Related: Onomatopoeic; onomatopoeial.
the naming of a thing or action by a vocal imitation of the sound associated with it (such as buzz or hiss). Onomatopoeia may also refer to the use of words whose sound suggests the sense. This occurs frequently in poetry, where a line of verse can express a characteristic of the thing being portrayed. In the following lines from Sylvia Plath's poem "Daddy," the rhythm of the words suggests the movement of a locomotive: An engine, an engine Chuffing me off like a Jew.A Jew to Dachau, Auschwitz, Belsen.