Pull out all the stops

Meaning

Make every possible effort.

Origin

The derivation of this phrase from the fact that pipe organs have stops which control the air flow and that pulling them out increases the volume seems to be the type of casual easy answer that is the hallmark of folk etymology. That is the source of the phrase though.

Prior to the introduction of pipe organs which contained stops the word 'stop' had, in this context, been used to mean 'note' or 'key'. That usage is recorded as early as the late 16th century, as in this example from George Gascoigne's satire The steele glas, 1576:

"But sweeter soundes, of concorde, peace, and loue, Are out of tune, and iarre in euery stoppe."

Of course, 'notes' and 'keys' can't be pulled out, whereas organ stops can.

The figurative use came to light in the in 1865, in Matthew Arnold's Essays in criticism:

"Knowing how unpopular a task one is undertaking when one tries to pull out a few more stops in that... somewhat narrow-toned organ, the modern Englishman."