Cheers fast time showing skill (6)
I believe the answer is:
talent
'skill' is the definition.
(talent can mean a skill or ability)
'cheers fast time' is the wordplay.
'cheers' becomes 'ta' (both can informally mean thank you).
'fast time' becomes 'lent' (I've seen this before).
'ta'+'lent'='TALENT'
'showing' is the link.
(Other definitions for talent that I've seen before include "Old coin for natural ability" , "Natural ability or aptitude" , "Innate skill" , "Natural endowment" , "some scouts are looking for" .)