Word Study
Sorus
CIDE DICTIONARY
Sorus, n. [NL., fr. Gr. a heap.].
- One of the fruit dots, or small clusters of sporangia, on the back of the fronds of ferns. [1913 Webster]
- In parasitic fungi, any mass of spores bursting through the epidermis of a host plant. [Webster 1913 Suppl.]
OXFORD DICTIONARY
Sorus, n. (pl. sori) Bot. a heap or cluster, esp. of spore-cases on the under-surface of a fern-leaf, or in a fungus or lichen.
Etymology
mod.L f. Gk soros heap
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