society > armed hostility > military equipment > operation and use of weapons > action of propelling missile > discharge of firearms > [noun] > line of fire (3)
Often used for ‘straight line’ (sense 9); esp. in Physics and technical, as in line of the apsides, line of distance, line of force, line of sight…
The notional line corresponding to the direction in which a gun is aimed; the (potential) path of gunfire, a missile, etc.; = line of fire at line…