import vs overtone

import and overtone both are nouns.

Word	Noun	Adjective	Verb	Adverb
import	Yes	No	Yes	No
overtone	Yes	No	No	No

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

import (noun)	overtone (noun)
commodities (goods or services) bought from a foreign country	a harmonic with a frequency that is a multiple of the fundamental frequency
having important effects or influence	(usually plural) an ulterior implicit meaning or quality
a meaning that is not expressly stated but can be inferred
the message that is intended or expressed or signified
an imported person brought from a foreign country

import (verb)	overtone (verb)
indicate or signify
bring in from abroad
transfer (electronic data) into a database or document