Muslim vs mujtihad

Muslim and mujtihad both are nouns.

Word	Noun	Adjective	Verb	Adverb
Muslim	Yes	Yes	No	No
mujtihad	Yes	No	No	No

As nouns, mujtihad is a hyponym of Muslim; that is, mujtihad is a word with a more specific, narrower meaning than Muslim:

Muslim: a believer in or follower of Islam
mujtihad: an Islamic scholar who engages in ijtihad, the effort to derive rules of divine law from Muslim sacred texts

Muslim (noun)	mujtihad (noun)
a believer in or follower of Islam	an Islamic scholar who engages in ijtihad, the effort to derive rules of divine law from Muslim sacred texts

Muslim (adjective)	mujtihad (adjective)
of or relating to or supporting Islamism