What does "nasty" mean?

Nasty: Hence, loosely: Offensive; disagreeable; unpropitious; wet; drizzling; as, a nasty rain, day, sky.

Additional senses

  1. 2.Characterized by obcenity; indecent; indelicate; gross; filthy. Anything nasty is usually wet or damp as well as filthy or dirty, and disgusts by its stickness or odor; but filthy and foul imply that a thing is filled or covered with offensive matter, while dirty describes it as defiled or sullied with dirt of any kind; as, filthy clothing, foul vapors, etc.

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