Question

What is drag define it

Answer 1

drag is the aerodynamic force that oppose an aircraft motion through the air

Answer 2

Drag is normally defined as pulling something.
However, in fluid dynamics, it means the resistance offered by the air or fluid on the body. For example, an airplane flying high up is affected by the air drag.
Hence, drag acts in the opposite direction of the motion of an object.
Types of drag :
Parasitic Drag
Lift-induced Drag
Wave Drag