ku-chiku vs bamboo

ku-chiku and bamboo both are nouns.

Word	Noun	Adjective	Verb	Adverb
ku-chiku	Yes	No	No	No
bamboo	Yes	No	No	No

As nouns, bamboo is a hypernym of ku-chiku; that is, bamboo is a word with a broader meaning than ku-chiku:

ku-chiku: large bamboo having thick-walled culms; native of China and perhaps Japan; widely grown elsewhere
bamboo: woody tropical grass having hollow woody stems; mature canes used for construction and furniture

ku-chiku (noun)	bamboo (noun)
large bamboo having thick-walled culms; native of China and perhaps Japan; widely grown elsewhere	woody tropical grass having hollow woody stems; mature canes used for construction and furniture
	the hard woody stems of bamboo plants; used in construction and crafts and fishing poles