Swot etymology in English

English word swot comes from Proto-Indo-European *sweyd-, and later Proto-Germanic *swait- (Sweat; blood.)

Dictionary entry	Language	Definition
*sweyd-	Proto-Indo-European (ine)	to sweat
*swoydo-	Proto-Indo-European (ine)
*swait-	Proto-Germanic (gem-pro)	Sweat; blood.
swat	Old English (ang)	Blood.
swāt	Old English (ang)
swat	Middle English (enm)
swot	English (en)	(intransitive, slang, British) To study with effort or determination.. (transitive, slang, UK, with up) To study something with effort or determination (swot up on). (slang, British) One who swots.. (slang, British) Vigorous study at an educational institution.. (slang, British) Work.

Swot etymology