Push the boat out

Meaning

To spend generously. To spend more than one is normally accustomed to doing, often to mark a special occasion.

Origin

This phrase originates with the literal meaning, i.e. pushing boats from wherever they are beached and into the water. People have for centuries built boats that were too large for an individual to move. Helping a seaman to push the boat out was an act of generosity - a similar to the modern-day act to helping to push a car that is broken down.

The phrase became used in UK nautical circles to mean 'buy a round of drinks' sometime during the 1930s. For example, in J. Curtis' You're in Racket, 1937:

"This bloke you're meeting up the Old Jacket and Vest to-night, let him push the boat out, the bastard. Surely he can pester for a tightener if you're hungry."

By 1946, John Irving had listed the term as Royal Navy slang, with that meaning - in Royal navalese: a glossary:

"Push the boat out, to, a boatwork term used to imply paying for a 'round of drinks'."

See also - Nautical Phrases.