In a song, a verse that is repeated regularly and often. Applicable to anything repeated with frequency and regularity.
Also to avoid taking an action, usually with some conflict.
"We all lived in a yellow submarine, a yellow submarine, a yellow submarine..."
Jennifer Lopez refrained from firing her personal aid even though her aid had brought her the wrong kind of coke twice now.
To stop. Often followed by 'from'. 'Refrain' is usually used when speaking about human action.
"Please refrain from using your cell phone in the restaurant, ma'am."
Normally he would have made a Tom Arnold joke at a moment like that, but he was able to refrain from doing so.