Chiefly Brit., Slang dirty, cheap, nasty, disgusting, etc.: a generalized term of disapproval
Origin of grotty; from grotesque + -y
adjectivegrot·ti·er, grot·ti·est Chiefly British Slang
Very unpleasant; miserable.
Origin of grottyAlteration of grotesque.
(comparative grottier, superlative grottiest)
Clipping of grotesque. Possibly from Scottish Gaelic grod (“rotten, putrid”).