Also see definition of "File" in Word Study
File [nave]
FILE, used for sharpening edged tools, 1 Sam. 13:21.FILE [isbe]
FILE - fil: Found only in 1 Sam 13:21, but the text here is obscure. The Hebrew (petsirah phim) signifies "bluntness of edge," and is so rendered in the Revised Version, margin.See TOOLS.
Also see definition of "File" in Word Study