A phrase that combines a verb with a preposition or adverb or both and that functions as a verb whose meaning is different from the combined meanings of the individual words.
Phrasal Verb:
rub something up
Meaning:
to raise something, such as the nap of a rug, by rubbing.
Example:
When you run the vacuum cleaner across the floor, you rub the nap of the rug up and get the dirt out.