A glass ship (8)
I believe the answer is:
schooner
This clue is a double definition.
'a glass' is the first definition.
(schooner is a kind of glass)
'ship' is the second definition.
(I've seen this before)
(Other definitions for schooner that I've seen before include "Item used for drinking" , "Swift sailing vessel - sherry glass" , "Sailing vessel - drinking vessel" , "Measure for sherry or kind of sailing ship" , "that carries sherry" .)