Final answer:
The word 'atlas' is derived from the Greek Titan Atlas, who according to mythology, held up the sky. This term was later used to refer to collections of maps.
Step-by-step explanation:
The word atlas is derived from the name of a person. In Greek mythology, Atlas was a Titan who was condemned to hold up the sky for eternity. The term eventually became associated with collections of maps, as a depiction of the entire world was seen as 'holding up' the world just like Atlas did. This evolved into the use of the word 'atlas' for a book of maps or charts.