topi vs pith helmet

topi and pith helmet both are nouns.

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

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

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

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

topi (noun)	pith 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