Rigorous

Meticulous

Synonyms: Meticulous, conscientious, diligent, ultra-careful, painstaking, precise, correct, studious, mathematical, perfectionist, particular, strict, fastidious, finicky, demanding, pedantic, pernickety, nice, laborious, punctilious, careful, attentive, scrupulous, exact, accurate, thorough, exhaustive, detailed, methodical, religious, fussy, hair-splitting, finical, exacting, nitpicking, persnickety, and overnice.

Strict

Synonyms: Strict, stern, austere, tough, harsh, cruel, relentless, inflexible, despotic, intransigent, demanding, severe, stringent, spartan, hard, rigid, savage, unsparing, authoritarian, draconian, uncompromising, and exacting.

Harsh

Synonyms: Harsh, bad, extreme, unpleasant, foul, filthy, blustery, wild, storm-tossed, heavy, raging, severe, bleak, inclement, disagreeable, nasty, stormy, squally, tempestuous, violent, heaving, and choppy.

Example Sentences

The training program is very rigorous.

They follow rigorous safety procedures always.

Her research requires rigorous analysis techniques.

The curriculum is rigorous and challenging.