objection vs demurral

objection and demurral both are nouns.

Word	Noun	Adjective	Verb	Adverb
objection	Yes	No	No	No
demurral	Yes	No	No	No

As nouns, demurral is a hyponym of objection; that is, demurral is a word with a more specific, narrower meaning than objection:

objection (noun)	demurral (noun)
(law) a procedure whereby a party to a suit says that a particular line of questioning or a particular witness or a piece of evidence or other matter is improper and should not be continued and asks the court to rule on its impropriety or illegality	(law) a formal objection to an opponent's pleadings
the act of protesting; a public (often organized) manifestation of dissent
the speech act of objecting
the act of expressing earnest opposition or protest