The most common and most likely answer to this crossword clue is the 4 letter word NODS
I've seen this crossword clue in The Daily Telegraph
N
O
D
S
More clues leading to the result NODS
- Agrees to one result of decimal coinage
- Silently indicates the difference between “forwards” and “bellicose”
- Not one detective gestures in agreement
- Agreeable gestures from daughter hugged by lad on the way back
- Ozes and rowses?
- Signs agreement without senior detective
- Signals assent to ban on games console?
- Signals agreement — name on document signed using initials only
- Acknowledges that head of state, a Spanish gent, is coming north
- Agrees on turning up and does, with no heart
Buddy explains!

The straight part
We know that "Agrees" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case agrees = nods.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 NODS mean?
NODS verb- To incline the head up and down, as to indicate agreement.
- To briefly incline the head downwards as a cursory greeting.
- To sway, move up and down.
- To gradually fall asleep.
- To signify by a nod.
- To make a mistake by being temporarily inattentive or tired
- To head; to strike the ball with one's head.
- To allude to something.
- To fall asleep while under the influence of opiates.