The most common and most likely answer to this crossword clue is the 5 letter word CHEEK
I've seen this crossword clue in The Sunday Telegraph
C
H
E
E
K
More clues leading to the result CHEEK
- Lip — part of the face
- Guerrilla starting to enrage king with insolence
- Chap with attitude
- Nerve — one of two on face
- Neck or lip, or nearby part of head
- Neck, lip or elsewhere
- Chap to show impertinence in intimate dancing style
- Lip's attached to it in other words
- After church, scream at sight of mouse's boldness
Buddy explains!

The straight part
We know that "Neck or lip/part of head" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case neck or lip/part of head = cheek.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 CHEEK mean?
CHEEK noun- The soft skin on each side of the face, below the eyes; the outer surface of the sides of the oral cavity.
- (usually in the plural) The lower part of the buttocks that is often exposed beneath very brief underwear, swimwear, or extremely short shorts.
- Impudence.
- One of the genae, flat areas on the sides of a trilobite's cephalon.
- One of the pieces of a machine, or of timber or stonework, that form corresponding sides or a similar pair.
- (in plural) The branches of a bridle bit.
- Either side of an axehead.
- The middle section of a flask, made so that it can be moved laterally, to permit the removal of the pattern from the mould.
- To be impudent towards.
- To pull a horse's head back toward the saddle using the cheek strap of the bridle.