This is the 3511th most frequent Korean word.
멕시코
Mexico.
Here, '멕시코' is used as a proper noun to refer to the country 'Mexico' in a geographic context.
나는 멕시코에 가고 싶어요.
I want to visit Mexico.
In this sentence, '멕시코' is used as an adjective modifying '음식', referring to food from Mexico or Mexican cuisine.
멕시코 음식은 정말 맛있어요.
Mexican food is really delicious.
'멕시코' functions as the possessive form '멕시코의', relating to the culture of Mexico.