Other forms: expelled, expelling, expels
To expel someone is to force them out officially and for good. A pupil expelled from school does not come back on Monday; a diplomat expelled from a country has to be on a plane by Friday.
The weight of the word comes from who does it — a headteacher, a government, a party, a club, someone with the power to decide. Bodies and machines expel too, and there it just means push out: you expel air from your lungs, a volcano expels ash, a pump expels water from the hull. The noun is expulsion, as in the expulsion of two students. Do not reach for expel over small things — your flatmate throws you out, a bouncer throws you out, and only a school or a state expels you.
1verbexpelTo officially force someone to leave a school, country or organisation.
“Two students were expelled after the fight.”
synonyms: banish, throw out
2verbairTo force air, liquid or waste out of a body or container.
“Take a deep breath and expel it slowly.”
Also accepted in games: kick out
Expel came into late Middle English from Latin expellere: ex-, out, joined to pellere. The root behind pellere is pel-, meaning beat — the same shove you can feel in propel, repel and compel. Expelling someone is not asking them to go; it is driving them out.
Proto-Indo-European
*pel- (beat)
Latin
expellere
English, today
expel
Late Middle English: from Latin expellere, from ex- + pellere.
Etymology from Wiktionary, CC BY-SA
Practised in Sharper Verbs, Hitting & Pushing