What does the idiom "Rank and file" mean?

• Rank and file
English Meaning: the ordinary members of an organization as opposed to its leaders.
Bangla Meaning: সাধারণ স্তরের।

Hence, the idiom "Rank and file" means - Ordinary members of a group.

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

Source: Lecture.