Sailing ship in strong wind about to cross lake (7)
I believe the answer is:
galleon
'sailing ship' is the definition.
(galleon is a kind of sailing ship)
'strong wind about to cross lake' is the wordplay.
'strong wind' becomes 'gale' (I've seen this in another clue).
'about' becomes 'on' (as in a book 'on' a certain topic).
'to cross' is an insertion indicator (some letters cross or go round others).
'lake' becomes 'L' (geographical abbreviation).
'gale'+'on'='galeon'
'galeon' going around 'l' is 'GALLEON'.
'in' is the link.
(Other definitions for galleon that I've seen before include "Spanish treasure ship" , "Historical warship with three or more masts" , "Large old sailing vessel" , "Large Spanish sailing ship of yore" , "Old Spanish war-ship" .)