noun which may take the genitive case particle 'no'
at work; working; in the middle of work
Describes the state of being engaged in work, often used with に or as a no-adjective. Common in phrases like 仕事中に (while working) or 仕事中です (I'm working).
仕事中に電話がかかってきた。
I got a phone call while I was working.
今、仕事中なので、後でかけ直します。
I'm working right now, so I'll call you back later.