homoplast

from The Century Dictionary.

• noun An organ or part corresponding in external form to another, though of distinct nature.
• noun That which is homoplastic, as any aggregate or fusion of plastids: opposed to alloplast.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Biol.) One of the plastids composing the idorgan of Haeckel; -- also called homoörgan.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun biology One of the plastids composing the "idorgan" of Ernst Haeckel.