Polysemy
The concept of metonymy also informs the nature of polysemy, i.e., how the same phonological form (word) has different semantic mappings (meanings). If the two meanings are unrelated, as in the word pen meaning both writing instrument and enclosure, they are considered homonyms.
Within logical polysemies, a large class of mappings may be considered to be a case of metonymic transfer (e.g., chicken for the animal, as well as its meat; crown for the object, as well as the institution). Other cases wherein the meaning is polysemous, however, may turn out to be more metaphorical, e.g., eye as in the eye of the needle.
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