probably from Italian puntiglioso, from puntiglio "fine point," from Latin punctum "prick" (see point (n.), also the source for punctual).
- The old prince, like all fathers indeed, was exceedingly punctilious on the score of the honor and reputation of his daughters. He was irrationally jealous over his daughters, especially over Kitty, who was his favorite. (Tolstoy - Anna Karenina)
- ‘Cyril Arthur Frewin – Saint Cyril – is a highly reliable, eminently conscientious, totally bald, incredibly boring clerk of the old school. Saint Cyril, though punctilious to a fault, has in my view reached his natural promotion ceiling in his line of country or profession. Saint Cyril is set in his ways. Saint Cyril does what he does, one hundred per cent. Amen.’ (le Carre - The secret pilgrim)