A specific type of Striking block which is physically distinguishable by both the inward and downward direction of movement and the upward facing of the palm of the hand (both in relation to the practitioner) in order to effect the block.

Comments:

The Inside Downward block travels in the reverse direction of the standard (outside) downward block.

This version of the inside downward block is most economically executed from a cocked position of the arms (i.e. hands up).

Derivation:

This block derives its name from the fact that it combines protecting the lower zone of the body, the outward motion, and rotational position of the fist (i.e. palm facing upward).

Historically speaking, this block was referred to as inside downward palm out. That name was eventually replaced (in the early 1970's) with inside downward palm up.