This is the 1818th most frequent Japanese word.
工
"工" means "craft," "construction," or "worker."
Here, '工' (kou) is part of the compound word '工場' (koujou), which means 'factory'. It conveys a place related to manufacturing or industry.
工場で働いています。
I work at a factory.
In the compound '工学' (kougaku), '工' refers to engineering or technical skills, as part of the academic or professional field.
彼は工学を専攻しています。
He specializes in engineering.
Within '工夫' (kufu), '工' signifies craftsmanship or creativity, used here to express ingenuity in construction or planning.