Holiday afloat for Tom? (6)
I believe the answer is:
cruise
I believe this is a double definition.
'holiday afloat' is the first definition.
(I've seen this before)
'tom?' is the second definition.
(Tom Cruise)
'for' acts as a link.
(Other definitions for cruise that I've seen before include "Holiday on liner" , "Sea trip" , "Shipboard holiday" , "Holiday afloat - Kidman's ex" , "Pleasure trip on ship" .)