Where does “Montclair” come from?

Montclair (English) comes from French clair, from Middle French cler, from Old French cler, from Latin clārus, from Proto-Indo-European ḱelh₁- — to warm up, to be hot; to warm up, be hot.

Ancestry of “Montclair”, step by step

Step	Language	Word	Meaning
1	French	clair	clear; light; clearly
2	Middle French	cler	bright, well-lit, not dark; clear
3	Old French	cler	bright, well-lit, not dark; clear
4	Latin	clārus	clear, bright
5	Proto-Indo-European	ḱelh₁-	to warm up, to be hot; to warm up, be hot

Every word from Proto-Indo-European ḱelh₁- →Every word from Latin clārus →Every word from Old French cler →