camel vs Arabian camel

camel and Arabian camel both are nouns.

Word	Noun	Adjective	Verb	Adverb
camel	Yes	No	No	No
Arabian camel	Yes	No	No	No

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

camel: cud-chewing mammal used as a draft or saddle animal in desert regions
Arabian camel: one-humped camel of the hot deserts of northern Africa and southwestern Asia

Other hyponyms of camel include Camelus dromedarius, dromedary, Bactrian camel, Camelus bactrianus.

camel (noun)	Arabian camel (noun)
cud-chewing mammal used as a draft or saddle animal in desert regions	one-humped camel of the hot deserts of northern Africa and southwestern Asia