To faff is to do much while achieving little. This can either be through procrastination, or because a job is inherently fiddly - a task that cannot be done without messing around at some length can be said to be 'a faff'. The verb is often used in the form 'faff around'.
'Faff' seems to be onomatopoeic - I imagine the sound someone's shirt makes as they flap their arms uselessly up and down, or the indistinct muttering they make as they go about their frustratingly unproductive attempts to get things done. Apparently the word can also mean 'a puff of wind,' or 'to blow in sudden gusts', but the OED only mentions this in the entry for 'faffle'. 'To faffle' can just mean 'to faff', but can also mean 'To stutter or stammer; to utter incoherent sounds', 'To saunter; to fumble', or 'Of a sail: To flap idly in the wind'. In the context of literally flapping, compare luff and bunt (which is what bunting does). The sense of stammering or babbling is intriguingly close to both maffle and waffle.
Although 'faffle' is attested as far back as 1570, and 'faff' from 1874, both are listed as dialect words, and generally considered informal. I don't know how widespread they are, but I would expect anyone in Britain to understand what I meant if I said I was faffing around, and I understand the word was used in an episode of the West Wing, so apparently it has some international reach - which is good, because it is one of my favourite words, and I know of no exact synonym. Pootle, putter, dilly-dally, dawdle, procrastinate and flap all get part of the way there, but none of them quite captures it. Perhaps closest of all is futz.
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