sklə̇ˈrōsh(ē)əm noun
Etymology: New Latin, from Greek sklērotēs hardness (from sklēros hard) + New Latin -ium — more at skeleton
1. plural sclero·tia -)ə
a. : a compact mass of hardened mycelium stored with reserve food material in various true fungi that is usually dark-colored, often has cells which are short and stout or irregular in shape, and when mature becomes detached and remains dormant until a favorable opportunity for growth when it either sends out hyphae or produces spore fruits
the ergot of rye is a sclerotium
b. : a waxy mass of protoplasm into which the plasmodium of a myxomycete is transformed during dry seasons
2. capitalized : a form genus of sterile fungi (order Mycelia Sterilia) including many that form sclerotia and some that cause blights or rots of plants