- Any member of a family of organelles found in the cytoplasm of plants and some protists, which are membrane-bounded and contain DNA. Plant plastids develop from a common type, the proplastid.
Definition from: Gene Ontology via Unified Medical Language System at the National Library of Medicine
- Any of various cytoplasmic organelles of photosynthetic cells that serve in many cases as centers of special metabolic activities.
Definition from: Merriam-Webster's Medical Dictionary by Merriam-Webster Inc.
See also Understanding Medical Terminology.