Loose is usually an adjective meaning not tight or not secured, and it rhymes with goose: "the handle is loose." Lose is a verb meaning to misplace something or to be defeated, and it rhymes with news: "don't lose your keys" or "we might lose the match." One o for the verb, two for the adjective.
The core difference
These are not variants of one word — they are separate words with different meanings, different parts of speech and different pronunciations. The confusion is purely visual, caused by that single doubled letter.
Using loose
Loose describes a state: not tight, not fixed, not confined, not exact.
- A screw is loose in the hinge.
- The dog got loose and ran into the field.
- These trousers are too loose around the waist.
- It's a loose translation rather than a literal one.
There is also a rarer verb to loose, meaning to release or unleash — "he loosed the arrow" — but in modern prose loosen or release does that job, and the verb loose reads as deliberately literary.
Using lose
Lose is always a verb, and it inflects: lose, loses, losing, lost.
- I always lose my umbrella on the train.
- If we lose this contract, we're in trouble.
- She's trying to lose weight before the wedding.
- Don't lose your temper.
The test
Say the sentence aloud. If the word rhymes with news or choose, spell it lose. If it rhymes with goose or moose, spell it loose.
If you cannot trust your ear, try substituting a form of the verb. If losing or lost would work in a rewritten version of the sentence — "we're losing the match," "we lost the match" — then you need lose. If instead you could substitute tight as the opposite, you need loose.
The memory trick
Lose has lost an o. That is the whole trick, and it works because the meaning of the word is built into it: something has gone missing from the spelling itself.
The mistake to watch for
The overwhelming direction of error is writing loose where lose is meant: "I don't want to loose my job," "we're going to loose." Spellcheckers will not flag it, because loose is a real word, so this one has to be caught by eye.
Watch the related forms too. The noun is loss ("a heavy loss"), the past tense is lost, and someone who loses is a loser — one o — while something slack is loosely attached. And note that loosen and unloose mean the same thing, which is a genuine oddity of English rather than a mistake.
Frequently Asked Questions
Is it 'loose weight' or 'lose weight'?
Lose weight. You are shedding it, and shedding is a verb, so it takes the single-o spelling. "Loose weight" would describe weight that is not tied down.
Which is right: 'nothing to lose' or 'nothing to loose'?
Nothing to lose. The phrase means there is nothing you can be deprived of, so it needs the verb. The tell is the word 'to' just before it — after 'to' you almost always want an infinitive verb, which points to lose.