/ Dictionary / Index A appressorium: Meaning and Definition of Find definitions for: ap•pres•so•ri•um Pronunciation: (ap"re-sôr'ē-um, -sōr'-), [key] — pl. -so•ri•a a flattened and thickened tip of a hyphal branch, formed by some parasitic fungi, that facilitates penetration of the host plant. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. appressed apprise Related Content Daily Word Quiz: stringent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language