What's the difference between pleonasm and pleonast?

Pleonasm

Definition:

• (n.) Redundancy of language in speaking or writing; the use of more words than are necessary to express the idea; as, I saw it with my own eyes.

Example Sentences:

• (1) Therefore the term "psychogenic pain sensation" seems to be a pleonasm at first sight.
• (2) A choice is necessary in all cases which takes into consideration the patient's interests and the cost of treatment and permits one to avoid pleonasms and illogical treatment.

Pleonast

Definition:

• (n.) One who is addicted to pleonasm.

Example Sentences:

• (1) On the other side, for intraductal carcinoma, axillary dissection seems to be pleonastic due to the low percentage of secondary deposits in axillary lymph-nodes (1-3%) in women operated on for intraductal carcinoma.