Zaman is a rank-and-file employe in his office. Here the idiom 'rank-and-file' refers to -

• Zaman is a rank-and-file employe in his office. Here the idiom 'rank-and-file' refers to - ordinary member.
Rank and file
English Meaning: the ordinary members of an organization as opposed to its leaders.
Bangla Meaning: সাধারণ স্তরের

Ex. Sentence: He is a rank-and-file soldier.
Bangla Meaning: সে একজন সাধারণ সৈন্য।

Source: Website lecture.