A distinct category of a strike which is physically distinguishable by striking with all the middle knuckles of the hand.

Comments:

A Half-knuckle can be thought of as a specialized punch where the first knuckles are replaced with the middle knuckles. Because of this the half-knuckle often can be used as a replacement for a punch.

One major difference between the punch and the half-knuckle is weapon hardness where the half-knuckle is less hard than the punch. Because of this fact, half-knuckles should be used for softer targets than the punch.

Another major difference between the punch and the half-knuckle is weapon shape where the half-knuckle has less height than the standard punch. Because of this the half-knuckle can fit into tighter spaces than the punch - such as the throat area.

The half-knuckle is often referred to as a half-fist.

Half-knuckles can be executed in vast array of directions (e.g. straight, side, up, down, etc.) and orientations (e.g. horizontal, vertical, inverted, etc.).

Additionally, half-knuckles can be executed with different Methods of Execution, including (but not limited to):

Thrust

Hammer

Hook

Roundhouse

Lift

Loop

Given the numerous potential options available to effect the maneuver, one can see that the potential for creating a list of all potential half-knuckles is daunting.

Derivation:

The term half-knuckle is taken from the physical characteristic of the strike making contact with the middle knuckles of the fingers - i.e. the half knuckles.

In the context of the half-fist nomenclature, half open hand / half closed hand (fist) - thus half-fist.