(law, transitive) To make a decision in an official capacity regarding some matter.

a quantum well incorporated in a quantum dot

(transitive) To test the look or fit of (a garment) by wearing it. / (transitive, slang) To attempt; to undertake.

(idiomatic) Something that attracts, gives pleasure, or encourages, especially sexually.

(intransitive, idiomatic) To formalize an agreement.

To rely on a single source (as of income), rather than diversifying.

(idiomatic) To act against one's own interests; to unintentionally behave self-destructively.

(idiomatic, intransitive) To be crazy or eccentric.

(idiomatic) To raise one's clenched fists in front of one's body and stand in a threatening or defiant manner, in preparation for a fistfight.

(idiomatic) To create a difficult situation whose unpleasant consequences one must now endure.