in donkeys

In an exceptionally long period of time. The phrase likely originated as the rhyming slang, shortened to simply "donkeys," of "donkey's ears" —where "ears" rhymes with "years" and alludes to the length of a donkey's ears. I haven't seen Jim in donkeys! How's he doing these days? We haven't gotten together like this in donkeys. I've missed you! I haven't worked one of these machines in donkey's, but I'll give it a shot!