Synonyms of the word

exacting

• adj. Making excessive demands; difficult to satisfy.
• adj. (of an action, task, etc) Requiring precise accuracy, great care, effort, or attention.
• adj. (of a person or organization) Characterized by exaction.
• v. present participle of exact.

demanding

• adj. Requiring much endurance, strength, or patience.
• v. present participle of demand.

exigent

• adj. Urgent; needing immediate action.
• adj. Demanding; needing great effort.
• n. (archaic) Extremity; end; limit; pressing urgency.
• n. (obsolete, Britain, law) The name of a writ in proceedings before outlawry.

fastidious

• adj. Excessively particular, demanding, or fussy about details, especially about tidiness and cleanliness.
• adj. Overly concerned about tidiness and cleanliness.
• adj. Difficult to please; quick to find fault.

stern

• adj. Having a hardness and severity of nature or manner.
• adj. Grim and forbidding in appearance.
• n. (nautical) The rear part or after end of a ship or vessel.
• n. (figuratively) The post of management or direction.
• n. The hinder part of anything.
• n. The tail of an animal; now used only of the tail of a dog.
• n. A bird, the black tern.

strict

• adj. Strained; drawn close; tight.
• adj. Tense; not relaxed.
• adj. Exact; accurate; precise; rigorously nice.
• adj. Governed or governing by exact rules; observing exact rules; severe; rigorous.
• adj. Rigidly interpreted; exactly limited; confined; restricted.
• adj. (botany) Upright, or straight and narrow; — said of the shape of the plants or their flower clusters.
• adj. Severe in discipline.