The first law of language is that there are no laws of language. The laws of language are not the laws of the dictionary. Dictionaries should not decree (except in Scrabble), they should track and report. A dictionary should be an agora where users can meet and find common ground on how a word can be used in light of its origins, the history of its usage, the evolution of its meaning. A dictionary deals in denotations, not connotations. But connotations steer the future course of the word; connotations eventually become denotations.
Poets go beyond denotations to consider a word in its full colorations: etymology, yes, but also its connotations, both public and personal to the poet. And the word as a unit of sound: its rhythm, sonority, how its consonants and vowels work together. A word is a social contract between the user of the moment and all users who preceded. Poets amend or even break the social contract. They extend the reach of the word to encompass and express the new reality of the present. Not just poets, so do doctors and engineers. (“The fingers of the surgeon search the body’s landmarks for the first incision.”). Poets do this consciously. The liberties they take are not countenanced by the dictionary. It is creative destruction.
A language is like a sea of pack ice: solid and motionless to the eye, but prone to drift under pressure and always in subtle motion.