Both forms are correct. Loose and lose are two correct spellings. Although both forms are very similar in writing and comparable in pronunciation (loose is pronounced as / lus / and lose as / luz /) they don’t have much more in common. These words have developed a few centuries apart. Loose dates back to the XII century when it evolved from Middle English los or loos. While lose is even older and was first recorded before the X century, probably originates from Middle English losen. These words also differ in the functions they have in a sentence. As lose is always a verb, loose is most commonly used as an adjective and less often as a verb or an adverb. As a result, the meanings also vary. Overall, lose and loose may look alike but are two totally different words, which should not be mistaken.

Correct spelling, see definition and examples below.

Correct spelling, see definition and examples below.

Definition of loose:
Adjective: not firmly fastened or held in place, not attached to something;
There is a loose shelf in the cupboard, be careful and don’t drop anything.
I have some loose pieces of paper if you need something for your notes.
– not fitting closely;
This shirt is too loose, I need a smaller size.
– not following the original closely;
We could go see this play, it is a loose adaptation of Romeo and Juliet, it may be interesting.
Verb: to express emotions in an uncontrolled way;
She loved to sing loudly to loose her excitement.
– to use a weapon;
In a practice round, I usually loose the bow about ten times.
– to make something less tight;
My tie strangles me, could you help me loose it?
Adverb: in a loose manner;
I prefer to buy nuts sold loose than in ready packages.

Definition of lose:
Verb: to not have something anymore because it was displaced or taken away by someone;
Better not lend her your books, because she will lose them just like mine.
He lost both of his parents lately.
– to cease having some feelings or have less of something;
She has lost most of her hair because of cancer treatment.
I am sorry I lost my patience, but your kids can drive me crazy.
– to not succeed in a game, a competition, an election, etc.;
Republican Party has already lost in most of the states, they can’t win this election.