Brief here? Lap dancing to entertain this writer (9)
I believe the answer is:
ephemeral
'brief' is the definition.
(I've seen this before)
'here? lap dancing to entertain this writer' is the wordplay.
'dancing' indicates an anagram.
'to entertain' indicates putting letters inside.
'this writer' becomes 'me' (the person who is writing these clues).
'here'+'lap'='herelap'
'herelap' anagrammed gives 'epheral'.
'epheral' placed around 'me' is 'EPHEMERAL'.
(Other definitions for ephemeral that I've seen before include "Fleeting, lasting only a short time" , "A mere help (anag) - short-lived" , "life's too short" , "Short-lived, passing quickly" , "staying for a little while" .)