jam vs earth up

jam is a noun but earth up is not a noun.

Word	Noun	Adjective	Verb	Adverb
jam	Yes	No	Yes	No
earth up	No	No	Yes	No

As verbs, earth up is a hyponym of jam; that is, earth up is a word with a more specific, narrower meaning than jam:

jam (noun)	earth up (noun)
deliberate radiation or reflection of electromagnetic energy for the purpose of disrupting enemy use of electronic devices or systems
preserve of crushed fruit
a dense crowd of people
informal terms for a difficult situation

jam (verb)	earth up (verb)
interfere with or prevent the reception of signals	block with earth, as after a landslide
crowd or pack to capacity
get stuck and immobilized
block passage through
crush or bruise
press tightly together or cram
push down forcibly