The definition of dirty is something soiled, unclean or impure.(adjective)
To dirty is to cause something to become unclean or impure.(verb)
When you get mud on the floor, this is an example of a situation where you dirty the floor.
See dirty in Webster's New World College Dictionary
Origin: ME dritti
See dirty in American Heritage Dictionary 4
adjective dirt·i·er, dirt·i·est
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