χοϊκός is a nice little Hellenistic adjective, meaning "made of earth" or "earthy" or "from dust," only appearing in the NT as far as I can recall. In fact, I think it is a unique Pauline word and may only appear in 1 Corinthians, in which St. Paul consistently uses it as an antonym to that which is heavenly.
Such is the case with the verse you quoted, which says: The first human was made of dust from the earth, the second human, the Lord, from heaven.
However, I'm pretty sure the critical text does not include ὁ Κύριος. The point is that Adam was earthy in origin while Christ was heavenly.
FYI, the much more commonly used cousins of χοϊκός are χῶμα (noun) and χόω (verb). χῶμα is used in the LXX in a similar phrase, e.g. Exodus 8.16 (the dust of the earth), and it is also used elsewhere in the LXX as the word for a garbage mound, or even a mound of dirt erected around a city.
As for pronunciation: Ho-i-kos. The diaeresis over the iota means it is its own syllable, not a diphthong.