appressoria

noun, plural ap·pres·so·ri·a [ap-re-sawr-ee-uh, –sohr-] /ˌæp rɛˈsɔr i ə, -ˈsoʊr-/. Mycology.

1. a flattened and thickened tip of a hyphal branch, formed by some parasitic fungi, that facilitates penetration of the host plant.

noun plural -ria (-rɪə)

1. botany a flattened hypha of a parasitic fungus that penetrates the host tissues