i Register
In some senses, percutient is marked as archaic. Watch for register when choosing this word.
adj
Striking; having the power of striking or hitting.
noun
That which has the power of striking.
Therefore proceeding upon our grounds before layed; to wit, that no body can be moved of it self; we may determine those motions to be naturall unto bodies which have constant causes, or percutients to make them alwayes in such bodies: […]