systema lymphaticum vs lymphatic vessel

systema lymphaticum and lymphatic vessel both are nouns.

Word	Noun	Adjective	Verb	Adverb
systema lymphaticum	Yes	No	No	No
lymphatic vessel	Yes	No	No	No

systema lymphaticum (noun)	lymphatic vessel (noun)
the interconnected system of spaces and vessels between body tissues and organs by which lymph circulates throughout the body	a vascular duct that carries lymph which is eventually added to the venous blood circulation