- A secondary involucre, as during the base of an umbel within a compound umbel.
- An involucre that types in the base of a flower group within a compound inflorescence.
- A partial, secondary, or small involucre. See Illust. of involucre.
- In botany, a secondary involucre in a compound cluster of flowers, as in many of the Umbelliferæ. See cut under inflorescence (fig. 9).