The most common and most likely answer to this crossword clue is the 7 letter word ATLASES
I've seen this crossword clue in The Guardian
A
T
L
A
S
E
S
More clues leading to the result ATLASES
- Books taking a time to get fantastic sales
- Very close to girl collecting English books
- Learner when in classes disregarding right books of charts
- Collected books of maps at jumble sales
- Collected charts fellow sailing in ocean brought back
- Sailor overboard presumably rejected navigation aids
- Coming from the East, sailor is absorbed in marine books
- Where you find countries manufacturing sea salt
- Guides recall sailor in his environment
- Arty loans Elsa odd reference books
Buddy explains!

The straight part
We know that "Collected books of maps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case collected books of maps = atlases.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 ATLASES mean?
ATLASES noun- A bound collection of maps often including tables, illustrations or other text.
- A bound collection of tables, illustrations etc. on any given subject.
- (especially of the human body) A detailed visual conspectus of something of great and multi-faceted complexity, with its elements splayed so as to be presented in as discrete a manner as possible whilst retaining a realistic view of the whole.
- A collection of top-dimensional subspaces, called charts, each homeomorphic to Euclidean space, which comprise the entirety of a manifold, such that intersecting charts' respective homeomorphisms are compatible in a certain way.
- The uppermost vertebra of the neck.
- One who supports a heavy burden; mainstay.
- A figure of a man used as a column; telamon.
- A sheet of paper measuring 26 inches by 34 inches.