Read the dictionary definition of rub. All definitions for this word.
1. the act of rubbing or wiping
1. he gave the hood a quick rub
2. an unforeseen obstacle
3. move over something with pressure
1. rub my hands
2. rub oil into her skin
4. cause friction
1. my sweater scratches
5. scrape or rub as if to relieve itching
1. Don't scratch your insect bites!