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ap·pres·so·ri·um

(ăp′rə-sôrē-əm)

n. pl. ap·pres·so·ri·a (-sôrē-ə)

The flattened tip of a hypha in various species of parasitic fungi, from which a filament emerges that penetrates the host's tissues.

[New Latin appressōrium, from Latin appressus, past participle of apprimere, to press down; see APPRESSED.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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