A specific type of Striking block which is physically distinguishable by both the inward and downward direction of movement and the downward 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 natural position of the arms (i.e. hands at sides).

Derivation:

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

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