Shriek getting cuts — might this foam have helped? (7,5)
I believe the answer is:
shaving cream
'might this foam have helped?' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'shriek getting cuts' is the wordplay.
'shriek' becomes 'scream' ('scream' can be a synonym of 'shriek').
'getting' becomes 'having' (having is a kind of getting).
'cuts' means one lot of letters goes inside another (a group of letters 'cuts' into another word).
'scream' going around 'having' is 'SHAVING CREAM'.
(Other definitions for shaving cream that I've seen before include "Facilitator of a razor" , "Male toiletry item for the face" , "It aids facial hair removal" , "Bathroom product" , "Highly pressurised stuff" .)