Once upon a time planes dropped only gravity bombs that just fell with the forward speed of the launching aircraft. These exploded directly under the aircraft (see all ww2 footage). Then were developed "retarded-fall" or delayed bombs with fins or parachutes so that the bomb's forward movment slowed and it exploded behind the aircraft (see vietnam footage of bombs with pop-out fins). Then came laser-guided "smart" bombs. So we now have "smart" bombs which are guided, "dumb" bombs which arent, and "retarded" bombs which are dumb bombs that slow down. We have accidentally fallen into pc trap where it can be difficult to use these terms.

Retarded fall "snakeye" bombs: https://youtu.be/3_RM19hOMo4