Book of maps or charts (5)
I believe the answer is:
atlas
This clue is a double definition.
'book of maps' is the first definition.
(synonyms)
'charts' is the second definition.
(I've seen this before)
(Other definitions for atlas that I've seen before include "The first cervical vertebra" , "Map collection" , "Album of maps" , "In Greek myth, a Titan made to support the heavens" , "One greatly burdened" .)