Something that fails miserably

Large, beautiful breasts that are keep well consealed and initially appear to be much smaller and less impressive than they actually are until unleashed.

Flop is synonymous to Akshay Kumar.
Akshay Kumar holds the record of maximum number of 80 Flops. Hence he is the perfect definition of flop.

When someone bails on you at the last minute.

when a basketball player falls unnecessarily, after little or no contact

The first three board cards dealt in Texas Hold 'em poker. This is the only true definition.

to cancel plans with your friends, family, bf/gf at the last minute