from
The Collaborative International Dictionary of English v.0.48
Q \Q\ (k[=u]),
the seventeenth letter of the English alphabet, has but one
sound (that of k), and is always followed by u, the two
letters together being sounded like kw, except in some words
in which the u is silent. See Guide to Pronunciation, [sect]
249. Q is not found in Anglo-Saxon, cw being used instead of
qu; as in cwic, quick; cwen, queen. The name (k[=u]) is from
the French ku, which is from the Latin name of the same
letter; its form is from the Latin, which derived it, through
a Greek alphabet, from the Ph[oe]nician, the ultimate origin
being Egyptian.
[1913 Webster] Etymologically, q or qu is most nearly related
to a (ch, tch), p, q, and wh; as in cud, quid, L. equus,
ecus, horse, Gr. ?, whence E. equine, hippic; L. quod which,
E. what; L. aquila, E. eaqle; E. kitchen, OE. kichene, AS.
cycene, L. coquina.
[1913 Webster]