Even members of yacht team excuse me! (4)
I believe the answer is:
ahem
'excuse me' is the definition.
(both might be said to get someone's attention)
'even members of yacht team' is the wordplay.
'even members of' indicates alternate letters (letters in even-numbered positions are used).
'team' becomes 'em' (I can't explain this - if you can you should believe this answer much more).
The alternate letters of 'yacht' are 'ah'.
'ah'+'em'='AHEM'
Can you help me to learn more?
(Other definitions for ahem that I've seen before include "Utterance of mild disapproval" , "call attracting attention" , "attempt to attract attention" , "Sound used to attract attention" , "Throat clearing sound to catch attention" .)