Cheap or tasteless articles, or plural of tat (to make lace by tatting); also informal for tattoos.
From Middle English 'tat,' possibly from Old Norse or Scandinavian roots meaning to tangle or knot. Originally referred to cheap goods or shabby items; the tatting (lacemaking) sense comes from the verb meaning to tie knots in lace.
The word 'tats' perfectly shows how slang abbreviations eventually become official dictionary entries—'tattoos' got shortened so much that 'tats' is now the primary form younger people use, making it one of the fastest-evolving words in English.
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