Other forms: teaching, taught, teaches
To teach is to help somebody learn something you know. Teach a class, teach French, teach somebody to drive. It is irregular: teach, taught, taught.
The pair to keep straight is teach and learn, and the error is universal: the teacher teaches and the student learns, and he learned me is wrong in standard English however common it is in dialect. Two patterns are both correct: teach somebody something, and teach somebody to do something. And there is a warning sense — that will teach him — which means he has suffered a consequence he deserved, and is said with satisfaction.
1verbteachTo help somebody learn something.~82%
“She taught him to swim in one summer.”
2verbworkTo work as a teacher.~16%
“He has taught at the same school for twenty years.”
3verbshowTo show somebody something through experience.~2%
“That year taught me not to lend money to friends.”
Shares are an estimate: a language model read 8 sentences found in the wild and placed 6 of them on a sense (2 were unclear) — a count of our sample, not a measurement of English.
teach is a way of passing on knowledge.
Old English taecan meant to show or point out, from a Proto-Indo-European root *deik-, to show — the same root as Latin dicere, to say, and English token and toe. Teaching was originally showing, and the word for a finger pointing became the word for a lesson.
Proto-Indo-European
*deyḱ- — to show
Proto-Germanic
*taikijaną — to show
Proto-West Germanic
*taikijan
Old English
tǣċan — to show, declare, demonstrate; teach, instruct, train; assign, prescribe, direct; warn; persuade
Middle English
techen
English, today
teach
From Middle English techen, from Old English tǣċan (“to show, declare, demonstrate; teach, instruct, train; assign, prescribe, direct; warn; persuade”), from Proto-West Germanic taikijan, from Proto-Germanic taikijaną (“to show”), from Proto-Indo-European deyḱ- (“to show”). Cognate with Scots tech, teich (“to teach”), German zeigen (“to show, point out”), zeihen (“accuse, blame”), Gothic 𐌲𐌰𐍄𐌴𐌹𐌷𐌰𐌽 (“to announce, declare, tell, show, display”), Latin dīcō (“speak, say, tell”), Ancient Greek δείκνυμι (“show, point out, explain, teach”), Sanskrit दिशति (“to point out, show, tell, teach”). More at token.
Etymology from Wiktionary, CC BY-SA