Where does “doolally” come from?

doolally (English) comes from English doolally tap, from English tap, from Middle English tappe, from Middle English tappen, from Old English tæppian, from Old English -ian, from Old English -ōjan, from Proto-West Germanic -ōn — he, she.

doolally (English): Insane, mad or eccentric

Definitions

  1. Insane, mad or eccentric

Ancestry of “doolally”, step by step

StepLanguageWordMeaning
1Englishdoolally tapCamp fever; by extension, madness, eccentricity;...
2EnglishtapA tapering cylindrical pin or peg used to stop...
3Middle EnglishtappeA spigot or plug for a hole or spout; A hole or...
4Middle EnglishtappenTo let fluids flow from a spout; To retail beer;...
5Old Englishtæppianto tap
6Old English-ianForms verbs from nouns and adjectives
7Old English-ōjan
8Proto-West Germanic-ōnCreates denominative verbs from nouns; Creates...
9Proto-Germanic-ōnąCreates denominative verbs from nouns; Creates...
10Proto-Indo-European-eh₂yétiCreates iterative/ frequentative/ intensive...
11Proto-Indo-European-yétiCreates intransitive, often deponent,...
12Proto-Indo-Europeanyé-
13Chichewaiyehe, she
Every word from Chichewa iye