dervish vs whirler

dervish and whirler both are nouns.

Word	Noun	Adjective	Verb	Adverb
dervish	Yes	No	No	No
whirler	Yes	No	No	No

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

dervish: an ascetic Muslim monk; a member of an order noted for devotional exercises involving bodily movements
whirler: a dervish whose actions include ecstatic dancing and whirling

Other hyponyms of dervish include whirling dervish.

dervish (noun)	whirler (noun)
an ascetic Muslim monk; a member of an order noted for devotional exercises involving bodily movements	a revolving mechanism
	a dervish whose actions include ecstatic dancing and whirling