Build up a holiday island, as you might say (7)
I believe the answer is:
accrete
'build up' is the definition.
(I've seen this before)
'a holiday island as you might say' is the wordplay.
I cannot quite see how this works, but
'a' is within the answer.
'island' could be 'crete' (Greek island) and 'crete' is present in the answer.
A single letter 'c' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for accrete that I've seen before include "get together" , "Form by coalescence" , "Get bigger" , "Grow together, unite" , "Grow by coalescence" .)