1. strict
I got it through my head that my parent's strict rules were for my own benefit.
stricter control
Produced to strict organic standards.
Strict security measures were in force.
Along with the plants, animal life, too, was developing in harmony with the strict requirements of the land.
Belinda tried strict diets, grueling exercise routines, and some sort of esoteric New Age detox, all amounting to nothing--she had curves, and that was that.
A strict father makes his children toe the line by thorough training.
Early American colonists often had extremely strict work ethics inspired by their unique take on Christianity.
I have amongst my relatives, a single one who sincerely lives righteously, has strict principles and pursues an ideal, but all my other relatives speak ill and make fun of him.
The wealthy, self-indulgent young man felt oddly drawn to the strict, ascetic life led by members of some monastic orders.
My parents were very strict with me when I was young. The school is an old-fashioned institution with strict discipline.
I think many pupils prefer teachers to be strict because there are fewer problems with discipline.
Jamie loves meat but his wife is a strict vegetarian.
strict rules/regulations
In the strict sense of the term, a true democracy has never existed, and never will exist. It is against natural order that the great number should govern and that the few should be governed.
2. rigorous
The argument is rigorous and coherent but ultimately unconvincing.
Our plan has to be rigorous in order to be successful.
rigorous testing/checking/methods
Definition if something is rigorous, it is careful and thorough
a rigorous analysis of defence needs
rigorous calculations
When a phone arrives at a recycling centre it goes through a rigorous testing process.
The top engineer put the car through a series of rigorous tests.
The thief or swindler who has gained great wealth by his delinquency has a better chance than the small thief of escaping the rigorous penalty of the law.