Portmanteau of Hardcore (intense, extreme) and Nana (affectionate name for grandmother, either one's own or a woman who is likely to be somebody else's. See Oma).

Adherents, despite being in the prime of life, exhibit values, affectations or behaviours stereotyped as only being performed by the elderly.

Examples of this may include excessive tea drinking, knitting, utilisation of a lap blanket, wearing suspenders or thick glasses instead of modern alternatives, or an interest/hobby that is out of fashion.

Often these affectations are more environmentally friendly or healthy than the perceived norm, such as baking one's own pies from home-canned fruit or crocheting a scarf for winter instead of turning up the heater. The usually require more effort than modern alternatives, hence the hardcore (extreme) reference.

The etymology of this term is female.

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