1. The alternation of two or more different forms in the life cycle of a plant or animal
   - alternation of generations, xenogenesis

Type of: organic phenomenon

• black sally
• black salsify
• black saltwort
• Black Sea
• black sea bass
• Black September
• Black September Movement
• black sheep
• black snakeroot
• black spleenwort
• black spot
• black spruce
• black squirrel
• black stork
• black stump
• black sumac
• black swan
• Black Tai
• black tea
• black tongue
• black tree fern
• black turnstone
• Black Vernacular
• Black Vernacular English
• black vomit