Plain English Meaning

When the airplane is banked into a turn, one wing is lower than the other. The rudder pedal on the side of that lower wing is called bottom rudder. Pressing it pushes the nose further around in the direction of the turn.

Full Definition

The rudder pedal on the inside of a turn — that is, the rudder pedal on the same side as the lower wing when the airplane is banked. Applying bottom rudder pushes the nose further into the direction of the turn and is a known contributor to a cross-control stall and incipient spin, particularly during a skidding turn from base to final.

Context Anchor

Seen in stall and spin awareness discussions, especially when describing skidding turns and low-speed turning errors.

Derivation

Called 'bottom' because in a the is the lower one — physically toward the bottom — and the rudder pedal on that side is therefore the 'bottom' pedal. The opposite pedal, on the side, is '.'