Allow the nippers to put in an appearance (6)
I believe the answer is:
teethe
'allow' is the definition.
Although both the answer and definition are verbs in their base form, I cannot understand how they can define each other.
'the nippers to put in an appearance' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'the' is 'eth' which is within the answer.
'put' could be 'tee' (teeing is a kind of putting) and 'tee' is present in the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for teethe that I've seen before include "Cut one's dental fixtures" , "Have initial trouble (as a baby?)" , "(Of baby) have gum pain" , "Cut one's primary dentition" , "Cut one's first incisors" .)