(Canada, US) A device at a gas station that dispenses gasoline.

(Australia, New Zealand) Under pressure to perform, e.g. at work or in a sports contest. / Used other than figuratively or idiomatically: see under, pump.

(biochemistry) The transport of sodium ions across biological membranes using the metabolic energy of ATP.

A water pump consisting of a series of buckets on a chain, wheel or drum.

(of a tyre etc) inflated / (by extension) oversized / (of water) raised by pumping / (of a person) tense with excitement or enthusiasm

A device that transfers thermal energy between spaces, usually between an enclosed space and the outdoors.

(biochemistry) Any protein in the membrane of a cell or mitochondrion whose function is to move protons across the membrane and thus establish an electrochemical potential.

(finance) A form of financial fraud where the fraudster buys stocks cheaply, generates excitement about those stocks to create a temporary price increase, then sells the stocks before the price goes back down.

(slang) To use a breast pump and then discard the milk, typically because one has had an infection, or has been drinking alcohol.

(idiomatic) To lift weights; to engage in weight or strength training.