chew over vs excogitate

chew over and excogitate both are verbs.

Word	Noun	Adjective	Verb	Adverb
chew over	No	No	Yes	No
excogitate	No	No	Yes	No

As verbs, chew over and excogitate are synonyms defined as:

Other synonyms of chew over include contemplate, meditate, mull, mull over, muse, ponder, reflect, ruminate, speculate, think over.

chew over (verb)	excogitate (verb)
reflect deeply on a subject	reflect deeply on a subject
	come up with (an idea, plan, explanation, theory, or principle) after a mental effort