Definition -
(1) (noun) Another name for a hypocorism, i.e. a nick name.
(2) (adjective) "Of the nature of a pet-name; pertaining to the habit of using endearing or euphemistic terms." (OED)

Etymology -
The word derives via Late Latin from the Greek hupokorizesthai, to call by endearing names (from the Greek hypo, secretly or beneath + korizesthai, to caress).

Oxford English Dictionary -
Its first citation is from 1796:
"Harry … is the free or hypocoristic name for Henry."
(Pegge Anonym. (1809) 98 )

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