They are called 'tube feet'.
Commonly called the Dregs, a word which can apply to any 'sediment'
Very close to the bottom of the cup.
From an Engineering standpoint, it is called a BEARING. In a cheap compass it is a simple PINPOINT in the Base, and a CUP on the bottom of the Needle.
It is down at the bottom, just above 1/4 cup
Simply, the ball must come to rest at the bottom of the cup for the ball to be holed.
The Stanley Cup that is presented to the players, has the seal of the Hockey Hall of Fame on the bottom. You can check the Wikipedia article about the Stanley Cup at http://en.wikipedia.org/wiki/Stanley_Cup
that means the cup can hold 220ml of water
a mirror cup that's on the bottom of the choice of grand prixes
The inside of a cup is called the cavity or the interior.
It is simply called the bottom
In Mario kart wii, they are the cups in the bottom row.(banana cup, shell cup, leaf cup, & the lightning cup)