religious order vs religious sect

religious order and religious sect both are nouns.

Word	Noun	Adjective	Verb	Adverb
religious order	Yes	No	No	No
religious sect	Yes	No	No	No

As nouns, religious order and religious sect are synonyms defined as:

religious order and religious sect: a subdivision of a larger religious group

Other synonyms of religious order include sect.

religious order (noun)	religious sect (noun)
a subdivision of a larger religious group	a subdivision of a larger religious group