i Register
In some senses, puritan is marked as derogatory. Watch for register when choosing this word.
noun
A puritanical person.
These new puritans have turned out to be surprisingly unskilled and inexperienced - very different from my generation who invented wife-swapping, orgies and free love in the late Sixties and early Seventies.
adj
Acting or behaving according to the Puritan morals (e.g. propagating modesty), especially with regard to pleasure, nudity and sex; ascetic.
A pietistic protestantism, rigid, self-righteous, unintellectual, obsessed with puritan morality to the point where hypocrisy was its automatic companion, dominated this desolate epoch.
noun
A member of a particular Protestant religious sect advocating greater purity and piety.