On the way home from work; returning from the office. Can be used as a noun or adverbial phrase (e.g., 'on my way home from work').
会社帰りに同僚と居酒屋に寄った。
On the way home from work I stopped by an izakaya with a colleague.
会社帰りの電車はいつも混んでいる。
The trains on the way home from work are always crowded.
彼女は会社帰りにスーパーで夕飯の材料を買った。
She bought ingredients for dinner at the supermarket on her way home from work.