Calyx and Hulls

Calyx noun - (botany) the whorl of sepals of a flower collectively forming the outer floral envelope or layer of the perianth enclosing and supporting the developing bud; usually green.

Hulls and calyx are semantically related. In some cases you can replace term "Hulls" with "Calyx", this nouns are similar.

Calyx and hulls are semantically related. You can use "Calyx" instead a noun "Hulls".