spit up vs cough up

spit up and cough up both are verbs.

Word	Noun	Adjective	Verb	Adverb
spit up	No	No	Yes	No
cough up	No	No	Yes	No

As verbs, spit up and cough up are synonyms defined as:

spit up and cough up: discharge (phlegm or sputum) from the lungs and out of the mouth

Other synonyms of spit up include cough out, expectorate, spit out.

As verbs, spit up and cough up are synonyms defined as:

Other synonyms of spit up include pony up.

spit up (verb)	cough up (verb)
discharge (phlegm or sputum) from the lungs and out of the mouth	discharge (phlegm or sputum) from the lungs and out of the mouth
give reluctantly	give reluctantly