Where does “odd” come from?

Odd comes from Middle English od, derived from Old Norse oddr, ultimately from Proto-Indo-European dʰeh₁-, a root of uncertain meaning.

odd (English): Differing from what is usual, ordinary or...

Definitions

odd traces back through two separate lines of ancestry.

Step	Language	Word	Meaning
1	Middle English	odde	inflection of od: ## weak singular ## strong/weak...
2	Old Norse	oddi	odd, third or additional number; triangle
3	Old Norse	-i	th
4	Latin	-ē	ly; used to form adverbs from adjectives
5	Latin	dis-	asunder, apart, in two; reversal, removal;...
6	Latin	calceus	shoe
7	Latin	calx	limestone; chalk; the finish line
8	Ancient Greek	χάλιξ	small stone, pebble; gravel, rubble

Step	Language	Word	Meaning
1	Middle English	ode	Alternative form of od
2	Frankish	*aud	—