Noun:

সহকারী প্রধান সৈন্যাধ্যক্ষ,

second in command's Usage Examples:

The underboss is second in command to the boss.

A second in command to a premier is designated as a vice-premier or deputy premier.

mission or deputy chief of mission (DCM) as the primary title for the second in command of a diplomatic mission.

sous-chef, (French: "under-chief of the kitchen") is a chef who is "the second in command in a kitchen; the person ranking next after the executive chef.

comprises eight soldiers led by a corporal with a lance corporal as second in command.

Synonyms:

direction; commandment; order; behest; bidding; dictation; commission; speech act; charge; countermand; open sesame; injunction; bid;

Antonyms:

antinode; node; end; beginning; middle;