An unofficial honor given for excellence in any field. 'Two thumbs up' is/are not contained to any profession/achievement, and, therefore, can be awarded for any outstandingaccomplishment.
Something users ask for on any youtube video that has a handful of million views, Usually means the top comments aren't in the slightest funny unlike other videos or youtube back in the day.
A term youtube users will submit in the comment section of a video of any song that is older than a year to let everybody know that because they listen to older music, they are special. As a result, people who feel the same give them thumbs up as was the original intention of the comment.
A thumbs-up brofist is the act of brofisting your brosef, possibly while drinking brooskis, while making a thumbs-up with your hand, and turning it sideways in a fluent motion.
"I was talking with my brosef over some beers, and when he chugged that brooski, a brofist wasn't enough. I made a thumbs-up, gave the signal, turned it sideways, and thumbs-up brofisted him.