The most common and most likely answer to this crossword clue is the 6 letter word BIREME
I've seen this crossword clue in The Times
B
I
R
E
M
E
More clues leading to the result BIREME
- Galley providing portion of lamb, I remember
- Brie munched by me in galley
- How paper may be sold, did you say, in old vessel?
- Did the crew of this ship get two bank holidays?
- Believe paper reported those rowing in this
- Reportedly, purchase paper vessel of yore
- Old warship with two sets of propellers
- It involves two banks in a row
- Old ship, one in German city, docked
- Purchase some sheets, it’s suggested, for boat
Buddy explains!

The straight part
We know that "galley" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case galley = bireme.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does BIREME mean?
BIREME noun- (history) an ancient galley having two banks of oars, one above the other.