(uncountable) Equipment or paraphernalia, especially that used for an athletic endeavor.

Clothing; garments.

(countable) A wheel with grooves (teeth) engraved on the outer circumference, such that two such devices can interlock and convey motion from one to the other; a gear wheel.

(countable, automotive, cycling) A particular combination or choice of interlocking gears, such that a particular gear ratio is achieved.

(countable, automotive) A configuration of the transmission of a motor car so as to achieve a particular ratio of engine to axle torque.

(aviation) Ellipsis of landing gear.

(uncountable, slang) Recreational drugs, including steroids.

(engineering, transitive) To provide with gearing; to fit with gears in order to achieve a desired gear ratio.

(engineering, intransitive) To be in, or come into, gear.

To dress; to put gear on; to harness.

(usually with to or toward(s)) To design or devise (something) so as to be suitable (for a particular type of person or a particular purpose).

(finance) To borrow money in order to invest it in assets.

(chiefly Liverpool) great or fantastic