(sports) To feel the burning sensation arising in a muscle being intensely exercised; often used as an exhortation to extend oneself in physical exercise.

(idiomatic) An instinct or intuition; an immediate or basic feeling or reaction without a logical rationale.

(informal, intransitive) To stealthily fondle someone in a sexual manner.

creating a feeling of anxiety or despair

Creating a feeling of happiness.

To encounter an uncomfortable situation.

(idiomatic, transitive) To grope someone, especially someone's breasts, in a sexual manner.

(idiomatic, with to-infinitive) To feel able without giving offense. / (as imperative, with to-infinitive) You have my permission. / (as imperative, in response) You have my permission.

(software, of an application, operating system, etc.) The combination of the visual design and behaviour of a user interface.

(transitive, idiomatic) To be confident in being able to do something. / (transitive, idiomatic) To have an inclination to do something.