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An acronym for "sorry, mate, I didn't see you." Used as a noun in reference to the defense put forward by a motorist who was unable to see a nearby cyclist or motorcyclist prior to a collision or near-collision. Usually used mockingly to imply that the motorist did not pay adequate attention to the road. Primarily heard in UK. On the way to work this morning, I nearly got killed by a lorry driver who wasn't looking at all. Classic SMIDSY—I'm lucky to be alive! This junction is an absolute deathtrap for motorcyclists. The speeds are too high and the visibility is so poor that it's always a smidsy waiting to happen.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.