Jack off
Definition 1 of 1
Pro Tip 1/3Slang Term
'Jack off' is a slang term and considered very casual and often vulgar. 
You wouldn't use 'jack off' in formal situations or in polite conversation.
Pro Tip 2/3Avoid in Public
Using 'jack off' in public or among strangers could be offensive or embarrassing. 
Talking about someone jacking off during a dinner can make people uncomfortable.
Pro Tip 3/3Gender Specific
'Jack off' specifically refers to male masturbation and is not used for females. 
She found her brother jacking off, not her sister.