Real Dictionary

puritanical
adjective: If you describe someone as puritanical, you mean that they have very strict moral principles, and often try to make other people behave in a more moral way.

puritanical in American English
of the Puritans or Puritanism
adjective: very strict in moral or religious matters, often excessively so; rigidly austere

puritanical in British English
adjective: strict in moral or religious outlook, esp in shunning sensual pleasures