Where does “unpreachable” come from?

unpreachable (English) comes from English preachable, from English preach, from Middle English prechen, from Old French prëechier, from Latin praedicō, from Latin dīcō, from Latin -tiō, from Latin dissertātiō — small stone, pebble; gravel, rubble.

unpreachable (English): Not preachable; impossible to preach

Definitions

Not preachable; impossible to preach

Ancestry of “unpreachable”, step by step

unpreachable traces back through two separate lines of ancestry.

via English preachable

Step	Language	Word	Meaning
1	English	preachable	Capable of being preached
2	English	preach	To give a sermon; To proclaim by public...
3	Middle English	prechen	to preach
4	Old French	prëechier	—
5	Latin	praedicō	to proclaim, declare publicly
6	Latin	dīcō	to say, talk, speak, utter, mention
7	Latin	-tiō	tion, -ation, -ing
8	Latin	dissertātiō	(spoken) dissertation, discourse, disquisition
9	Latin	dissertus	arranged, disposed; explained
10	Latin	disserere	second-person singular future passive indicative...
11	Latin	dis-	asunder, apart, in two; reversal, removal;...
12	Latin	calceus	shoe
13	Latin	calx	limestone; chalk; the finish line
14	Ancient Greek	χάλιξ	small stone, pebble; gravel, rubble

via English un

Step	Language	Word	Meaning
1	English	un	One

Every word from Ancient Greek χάλιξ →Every word from Latin -tiō →Every word from Latin dis- →