Where does “extensionlessness” come from?

extensionlessness (English) comes from English extensionless, from English Extension, from Middle English extensioun, from Old French estension, from Latin extensio, from Latin -tiō, from Latin dissertātiō, from Latin dissertus — small stone, pebble; gravel, rubble.

extensionlessness (English): Lack of extension

Definitions

Lack of extension

Ancestry of “extensionlessness”, step by step

extensionlessness traces back through two separate lines of ancestry.

via English extensionless

Step	Language	Word	Meaning
1	English	extensionless	Lacking a file extension
2	English	Extension	The act of extending; a stretching out; enlargement in length, breadth, or time; an increase
3	Middle English	extensioun	—
4	Old French	estension	—
5	Latin	extensio	extension, stretching; swelling, tumour
6	Latin	-tiō	tion, -ation, -ing
7	Latin	dissertātiō	(spoken) dissertation, discourse, disquisition
8	Latin	dissertus	arranged, disposed; explained
9	Latin	disserere	second-person singular future passive indicative...
10	Latin	dis-	asunder, apart, in two; reversal, removal;...
11	Latin	calceus	shoe
12	Latin	calx	limestone; chalk; the finish line
13	Ancient Greek	χάλιξ	small stone, pebble; gravel, rubble

via English Ness

Step	Language	Word	Meaning
1	English	Ness	An Ulster princess and the mother of Conchobar mac Nessa and Findchoem in the Ulster Cycle of Irish mythology. Daughter of Eochaid Sálbuide. Also the mother of Cormac Cond Longas by incest with Conchobar mac Nessa
2	Middle English	nesse	—
3	Old English	næs	not, not at all; not; first/third-person singular...
4	Proto-Germanic	nasją	foothill; headland; cape
5	Proto-Indo-European	néh₂s	nose

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