topi vs sun helmet

topi and sun helmet both are nouns.

Word	Noun	Adjective	Verb	Adverb
topi	Yes	No	No	No
sun helmet	Yes	No	No	No

As nouns, topi and sun helmet are synonyms defined as:

topi and sun helmet: a lightweight hat worn in tropical countries for protection from the sun

Other synonyms of topi include pith hat, pith helmet, topee.

topi (noun)	sun helmet (noun)
a large South African antelope; considered the swiftest hoofed mammal	a lightweight hat worn in tropical countries for protection from the sun
a lightweight hat worn in tropical countries for protection from the sun