The most common and most likely answer to this crossword clue is the 6 plus 2 letter word THUMBS UP
I've seen this crossword clue in The Guardian
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More clues leading to the result THUMBS UP
- OK, let’s get ready to hitchhike!
- In general, very small drink is a hopeful sign
- Matter raised after hitch gets approval
- Tom’s family are revolting? Yes
- Encouragement to beat about the bush, almost wildly
- Tom with half of meal giving sign of approval?
- Green light for doctor entering in this way at Oxford, say
- About the potential bus strike, a good sign
- Approval as Tom maybe gets drink
Buddy explains!

The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does THUMBS UP mean?
THUMBS UP noun- A gesture signifying approval or okay; a thumb pointing up out of a fist.
- An approval or okay.
- To approve with a thumbs-up sign.