Where does “quasi” come from?

Quasi comes from Latin quasi, from qua and cum, both meaning "as" and "with," combined to express "as if."

quasi (English): resembling or having a likeness to something

Definitions

Step	Language	Word	Meaning
1	Latin	quasi	as if; as
2	Latin	quā	where
3	Latin	quī	who, that, which, what
4	Latin	-cumque	Used to derive indefinite adjectives, adverbs and...
5	Latin	cumque	however, whenever, howsoever, whensoever
6	Latin	cum	with, along with; at; -fold
7	Old Latin	com	Alternative form of cum
8	Proto-Italic	kom	with, along, at
9	Proto-Indo-European	ḱóm	beside, near, by, with
10	Proto-Indo-European	ḱe	Deictic particle, here; Post-positional...
11	Middle English	kyt	—
12	German	kitt	putty certain kinds of cement used for fixing e.g. window panes
13	Old High German	kuti	—
14	Proto-West Germanic	kwidu	gum, resin
15	Proto-Germanic	kweduz	resin
16	Proto-Indo-European	gʷet-	resin, gum; to say, speak
17	Proto-Indo-European	gū-	to bend; curve; arch; vault; to bow, bend, arch,...