drupe (n.)

also *dreu-, Proto-Indo-European root meaning "be firm, solid, steadfast," with specialized senses "wood," "tree" and derivatives referring to objects made of wood.

It forms all or part of: betroth; Dante; dendrite; dendro-; dendrochronology; dour; Druid; drupe; dryad; dura mater; durable; durance; duration; duress; during; durum; endure; hamadryad; indurate; obdurate; perdurable; philodendron; rhododendron; shelter; tar (n.1) "viscous liquid;" tray; tree; trig (adj.) "smart, trim;" trim; troth; trough; trow; truce; true; trust; truth; tryst.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit dru "tree, wood," daru "wood, log, timber;" Greek drys "oak," drymos "copse, thicket," doru "beam, shaft of a spear;" Old Church Slavonic drievo "tree, wood," Serbian drvo "tree," drva "wood," Russian drevo "tree, wood," Czech drva, Polish drwa "wood;" Lithuanian drūtas "firm," derva "pine, wood;" Welsh drud, Old Irish dron "strong," Welsh derw "true," Old Irish derb "sure," Old Irish daur, Welsh derwen "oak;" Albanian drusk "oak;" Old English treo, treow "tree," triewe "faithful, trustworthy, honest."

Proto-Indo-European root meaning "to cook, ripen." 

It forms all or part of: apricot; biscuit; charcuterie; concoct; concoction; cook; cuisine; culinary; decoct; decoction; drupe; dyspepsia; dyspeptic; eupeptic; kiln; kitchen; peptic; peptide; peptone; precocious; pumpkin; ricotta; terra-cotta.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit pakvah "cooked, ripe;" Avestan -paka- "cooked;" Greek peptein "to cook, ripen, digest," pepon "ripe;" Latin coquere "to cook, prepare food, ripen, digest, turn over in the mind," Oscan popina "kitchen;" Lithuanian kepti "to bake, roast;" Old Church Slavonic pecenu "roasted;" Welsh poeth "cooked, baked, hot."

"resembling or relating to a drupe or drupes," 1773; see drupe + -aceous.