puritanical

1. Rigorous in religious observance; marked by stern morality.
2. Puritanical Of, relating to, or characteristic of the Puritans.

adjective

Marked by excessive concern for propriety and good form: bluenosed, genteel, old-maidish, precise, priggish, prim, prissy, proper, prudish, strait-laced, stuffy, Victorian. Idioms: prim and proper. See plain/fancy.

Definition: moralistic
Antonyms: broad-minded, permissive

The adjective has 2 meanings:

Meaning #1: exaggeratedly proper
  Synonyms: priggish, prim, prissy, prudish, square-toed, straitlaced, straightlaced, tight-laced, victorian

Meaning #2: morally rigorous and strict
  Synonyms: blue, puritan, puritanic