What does appendage mean?
The definition of appendage
Ap*pend”age, n.
1 Something appended to, or accompanying, a principal or greater thing, though not necessary to it, as a portico to a house. Modesty is the appendage of sobriety. Jer. Taylor.
2 (Biol.)
A subordinate or subsidiary part or organ; an external organ or limb, esp. of the articulates. Antennæ and other appendages used for feeling. Carpenter.

Synonyms
— Addition; adjunct; concomitant.