Foreign Country, Other Countries, Overseas
noun, の adjective
An outside country is one outside of your own country. That is a foreign country, other countries, or overseas.
がいこく
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
まだ外国に行ったことがありません。
I have never been to a foreign country yet.
日本生まれの母にとって、「ハグ」は外国の文化です。
For my Japanese-born mother, “hugging” is a foreign culture.
ホノルルは、あまり外国っていう気がしません。
Honolulu doesn't feel like a foreign country.