Verb: becoming gray or turning gray in color (especially of hair, people, or objects). Noun: the process or state of becoming gray.
Present participle of 'grey,' from Old English 'graeg'; the verb is formed regularly by adding '-ing' to create the continuous or gerund form.
The phrase 'greying population' has become a statistical term in demography—as people live longer, societies face a demographic shift where older people outnumber younger ones!
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