Nearly all notice guy rolling big cheeses (5)
I believe the answer is:
names
'big cheeses' is the definition.
Although both the answer and definition are verbs in their -s form, I cannot see how one could define the other.
'nearly all notice guy rolling' is the wordplay.
'nearly all' means to remove the last letter (most but not all of the word).
'notice' becomes 'see' (notice can mean to spot or see).
'guy' becomes 'man' (guy can informally mean a man).
'rolling' shows that the letters should be reversed in order.
'see' with its final letter taken off is 'se'.
'se'+'man'='seman'
'seman' in reverse letter order is 'NAMES'.
Can you help me to learn more?
(Other definitions for names that I've seen before include "identification" , "Appellations or identifiers" , "Some people drop these to sound important" , "celebrities" , "Heroes" .)