intertwine vs splice

intertwine is not a noun while splice is a noun.

Word	Noun	Adjective	Verb	Adverb
intertwine	No	No	Yes	No
splice	Yes	No	Yes	No

As verbs, splice is a hyponym of intertwine; that is, splice is a word with a more specific, narrower meaning than intertwine:

Other hyponyms of intertwine include wind, wreathe, wattle, plash, pleach, knot, ravel, tangle.

intertwine (noun)	splice (noun)
	joint made by overlapping two ends and joining them together
	a junction where two things (as paper or film or magnetic tape) have been joined together

intertwine (verb)	splice (verb)
spin, wind, or twist together	join by interweaving strands
make a loop in	join the ends of
make lacework by knotting or looping	join together so as to form new genetic combinations
	perform a marriage ceremony