The little bar at the end of the line (5)

I believe the answer is:

serif

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'line' is the definition.
(I know that serif is a type of line)

I can't explain the rest of the clue.

(Other definitions for serif that I've seen before include "Line on written letters" , "Little bit of character" , "One feature of text" , "Projection on a letter in some fonts" , "decorative line" .)

I've seen this clue in the Evening Standard.

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