in-migration vs aliyah

in-migration and aliyah both are nouns.

Word	Noun	Adjective	Verb	Adverb
in-migration	Yes	No	No	No
aliyah	Yes	No	No	No

As nouns, aliyah is a hyponym of in-migration; that is, aliyah is a word with a more specific, narrower meaning than in-migration:

in-migration: migration into a place (especially migration to a country of which you are not a native in order to settle there)
aliyah: (Judaism) immigration of Jews to Israel

in-migration (noun)	aliyah (noun)
migration into a place (especially migration to a country of which you are not a native in order to settle there)	(Judaism) immigration of Jews to Israel
	(Judaism) the honor of being called up to the reading desk in the synagogue to read from the Torah