Caesar = "severed"
1) the surname of Julius Caesar, which adopted by Octavius Augustus and his successors afterwards became a title, and was appropriated by the Roman emperors as part of their title
Part of Speech: noun masculine
Of Latin origin; Caesar, a title of the Roman emperor: - Csar.
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root Καῖσαρ; click on the second column to search for that grammatical form of the root Καῖσαρ; click on the third column to search for that word and grammatical form; click on the total to search for the root Καῖσαρ.