see Q.

before vowels quad- (before -p- often quadru-, from an older form in Latin), word-forming element used in compounds of Latin origin and meaning "four, four times, having four, consisting of four," from Latin quadri-, which is related to quattor "four" (from PIE root *kwetwer- "four").

word-forming element meaning "four, having four, consisting of four," a variant of quadri- which was used in Latin especially before -p-, from an older form of the element which perhaps was influenced later by tri-.

word-forming element used since 18c. (but most productively in 20c.), "kind of, like but not really, as if," expressing some resemblance but implying a degree of fictitious or unreal quality or lack of some important feature; from Latin quasi "as if, as it were" (see quasi).

before vowels quinqu-, word-forming element from classical Latin meaning "five, consisting of or having five," from Latin quinque "five" (by assimilation from PIE root *penkwe- "five").