sori

Webster's Dictionary (GCIDE)

Sori \So"ri\, n., pl. of Sorus. [1913 Webster]

Sorus \So"rus\, n.; pl. Sori. [NL., fr. Gr. ? a heap.]

1.(Bot.) One of the fruit dots, or small clusters of sporangia, on the back of the fronds of ferns. [1913 Webster]

2. (a) In parasitic fungi, any mass of spores bursting through the epidermis of a host plant. (b) In lichens, a heap of soredia on the thallus. [Webster 1913 Suppl.]