Where does “tidy” come from?

Tidy comes from Middle English tidy, of uncertain origin and meaning.

tidy (English): Arranged neatly and in order; Not messy; neat and...

Definitions

Step	Language	Word	Meaning
1	Middle English	tidy	—
2	English	tide	The periodic change of the sea level,...
3	Middle English	tyde	—
4	Old English	tīd	time, period, season; period, season, time;...
5	Proto-Germanic	tīdiz	time; period, interval
6	Proto-Indo-European	déh₂itis	interval, period of time
7	Proto-Indo-European	deh₂y-	to share, divide
8	Proto-Indo-European	deh₂-	to share, divide

tidy — Etymology, Origin & Word History | Etymology Explorer