rub
noun
an unforeseen obstacle
the act of rubbing or wiping
“he gave the hood a quick rub”
Synonymswipe
verb
move over something with pressure
“rub my hands”
“rub oil into her skin”
cause friction
“my sweater scratches”
scrape or rub as if to relieve itching
“Don't scratch your insect bites!”
Source: WordNet 3.1, Princeton University