means Feeling deep satisfaction or pleasure in one's own achievements, qualities, or those of someone close — or, in the older sense, holding an inflated sense of one's own importance.

from From Old English 'prud' or 'prut,' meaning arrogant or haughty, which English likely borrowed from Old French 'prud,' 'prod' (brave, valiant) — itself from Late Latin 'prode' (advantageous, useful), a cousin of 'prodesse,' to be of benefit. There's a nice irony in the lineage: the word that came to mean overweening self-regard grew from a root about being genuinely useful and worthy. Curiously, English took the negative spin while the French branch kept the flattering one, giving us the borrowed 'prude' and 'proud' as estranged relatives.