The phrase clapped out comes from Victorian english. A time when there was a lot of poverty and a lot of working girls. Also a time before condoms were widely used. So the girls would eventually contract STD’s colloquially called the clap. When she was
so far infected that she was no longer able to work she was said to be clapped out. Nowadays this is jargon for anything old, worn out and unfit for use anymore.
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