The Collaborative International Dictionary
lowercase \low"er*case`\, Lower-case \Low"er-case`\, a. (Print.) Pertaining to, or kept in, the lower case; -- used to denote the small letters, in distinction from capitals and small capitals; as, lowercase letters a and b and c etc.. Contrasted with uppercase. See the Note under 1st Case, n., 3.
Douglas Harper's Etymology Dictionary
Wiktionary
a. (alternative spelling of lowercase English)
Usage examples of "lower-case".
Start under W, Goudy 24 point upper and lower: lower-case w,a,s,t,e, capital N,e,r,v,e, hyphen, capital P,o,w,e,r, screamer.
It would tire you to remember that DO meant b, TU o, and RO y, and that to say he-boy you must prefix the ape masculine gender sound BU before the entire word and the feminine gender sound MU before each of the lower-case letters which go to make up boy--it would tire you and it would bring me to the nineteenth hole several strokes under par.