Phrasal verbs are two or more words that together act as a completely new verb with a meaning separate from those of the original words.
rub something out
to obliterate something by rubbing.
See if you can rub those stains out.
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
A compilation of 50 phrasal verbs.