What's the difference between copartner and copartnership?

Copartner

Definition:

(n.) One who is jointly concerned with one or more persons in business, etc.; a partner; an associate; a partaker; a sharer.

Example Sentences:

(1) The exchange is stimulated by the addition of catalytic amounts of copartner of transaminations reaction.

Definition:

(n.) The state of being a copartner or of having a joint interest in any matter.
(n.) A partnership or firm; as, A. and B. have this day formed a copartnership.

Example Sentences: