an identifying name given to an electronically stored computer file, conforming to limitations imposed by the operating system, as in length or restricted choice of characters.
British Dictionary definitions for file name
filename
/ˈfaɪlˌneɪm/
noun
1.
an arrangement of characters that enables a computer system to permit the user to have access to a particular file
file name in Science
filename
(fīl'nām') A name given to a computer file to distinguish it from other computer files. Filenames often contain an extension that classifies the file by type.