earth tremor vs quake

earth tremor and quake both are nouns.

Word	Noun	Adjective	Verb	Adverb
earth tremor	Yes	No	No	No
quake	Yes	No	Yes	No

As nouns, quake is a hypernym of earth tremor; that is, quake is a word with a broader meaning than earth tremor:

earth tremor: a small earthquake
quake: shaking and vibration at the surface of the earth resulting from underground movement along a fault plane or from volcanic activity

Other hypernyms of earth tremor include earthquake, seism, temblor.

earth tremor (noun)	quake (noun)
a small earthquake	shaking and vibration at the surface of the earth resulting from underground movement along a fault plane or from volcanic activity

earth tremor (verb)	quake (verb)
	shake with fast, tremulous movements
	shake with seismic vibrations