word-forming element used since 18c. (but most productively in 20c.) and typically meaning "kind of, resembling, like but not really, as if;" from Latin quasi "as if, as it were," from PIE root *kwo-, stem of relative and interrogative pronouns
quartz
quartzite
quasar
quash
quasi
quasi-
quasimodo
quaternary
Quatorze
quatrain
quatrefoil