Japan Trench vs trench

Japan Trench and trench both are nouns.

Word	Noun	Adjective	Verb	Adverb
Japan Trench	Yes	No	No	No
trench	Yes	No	Yes	No

Japan Trench (noun)	trench (noun)
a depression in the floor of the Pacific Ocean to the northeast of Japan that reaches depths of 30,000 feet	a ditch dug as a fortification having a parapet of the excavated earth
	any long ditch cut in the ground
	a long steep-sided depression in the ocean floor

Japan Trench (verb)	trench (verb)
	cut or carve deeply into
	dig a trench or trenches
	cut a trench in, as for drainage
	fortify by surrounding with trenches
	set, plant, or bury in a trench
	impinge or infringe upon