Keelefilosoofia raamat
"Level" in "carpenter's level," meaning the tool, is certainly dead; there is no
other term for that tool, and in a dictionary it would be listed as a separate
meaning of the word.
However, as has been emphasized by Lakoff and Johnson (1980), the
distinction between novel or fresh metaphor and "dead" metaphor is one
of smooth degree, not of kind. Fresh metaphors get picked up and become
current, and then only very gradually--sometimes over centuries--sicken,
harden, and die.
(Exactly how many expressions in the previous paragraph were used
metaphorically rather than literally, assuming the distinction is not one of
degree?)
So it seems intellectual honesty requires us to confront metaphor.
The issues, and two simple theories
There is some variation in taxonomy as to how metaphor is classified with
respect to other figures of speech. Some theorists use the term "metaphor"
very broadly, as almost synonymous with "figurative
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