verb

• (transitive) To make equal; to cause to correspond in amount or degree.
• (obsolete, transitive) To be equal to; to equal, to rival.
• (intransitive, sports) To make the scoreline equal by scoring points.
• (underwater diving) To clear the ears to balance the pressure in the middle ear with the outside pressure by letting air enter along the Eustachian tubes.
• (category theory) Said of a morphism: to pre-compose with each of a parallel pair of morphisms so as to yield the same composite morphism.
• (signal processing) To adjust the balance between frequency components within an electronic signal.