Popular drink imbibed on vacation is tasteless (7)
I believe the answer is:
insipid
'tasteless' is the definition.
(synonyms)
'popular drink imbibed on vacation' is the wordplay.
'popular' becomes 'in'.
'drink' becomes 'sip' (sipping is a kind of drinking).
'on vacation' says to hollow out the word (remove centre letters).
'imbibed' with its centre taken out is 'id'.
'in'+'sip'+'id'='INSIPID'
'is' acts as a link.
(Other definitions for insipid that I've seen before include "Lacking flavour or banal" , "Tasteless" , "Wishy-washy" , "Lacking in flavour or interest" , "Colourless" .)