dóru

A PIE nominal root meaning "tree, wood," continued in Greek dóry (δόρυ, "wood, spear") and déndron (‌​‌​‌​‍​‌​‌​‍​‍​‍​‌​‌​‌​‌​‌​‌​‌​‌​‌​‌​‌​‍​‌​‌​‌​‍​‌​‍​‍​‍​‌​‍​‌δένδρον, "tree"), whence dendrite and rhododendron; Sanskrit dā́ru ("wood"); English tree; and the Celtic compound *dru-wid- ("oak-knower"), whence druid.

Discussion

The root *dóru ("tree, wood") is reconstructed from Greek dóry (δόρυ, "wood, spear, beam"), déndron ‌​‌​‌​‍​‌​‌​‍​‍​‍​‌​‌​‌​‌​‌​‌​‌​‌​‌​‌​‌​‍​‌​‌​‌​‍​‌​‍​‍​‍​‌​‍​‌(δένδρον, "tree," a reduplicated form), Sanskrit dā́ru ("wood, timber"), Avestan dāuru- ("wood"), Old English trēow ("tree"), Gothic triu ("wood, stick"), Old Irish daur ("oak"), and Welsh derwen ("oak"). Pokorny (IEW 214–217) and Mallory & Adams (EIEC s.v. *dóru) provide full documentation.

Greek dóry (δόρυ, "wood, beam, spear shaft") shows the common IE semantic extension from "wood" to "spear" (the weapon being named for its material). The reduplicated form déndron (δένδρον, "tree") gave the combining form dendro-: dendrite ("tree-like branching"), dendrochronology ("tree-ring dating"), and rhododendron ("rose-tree"). The dryad (dryas, δρυάς, "tree nymph") derives from drŷs (δρῦς, "oak, tree").

The Celtic compound *dru-wid- ("oak-knower" or "tree-knower") gave druid, one of the most culturally resonant borrowings from Celtic into English. The first element preserves the PIE tree-word; the second derives from *weyd- ("to see, to know"). Old Irish daur ("oak") and Welsh derwen ("oak") continue the simple root.

English tree descends from Old English trēow, with regular sound changes from PIE *dóru. The apparently vast difference between tree and dendrite illustrates how systematic sound laws can make cognates unrecognizable to non-specialists.

Sanskrit dā́ru ("wood, timber") appears in Vedic literature; the related dāru-há- ("woodcutter") is a compound. The root is important for PIE cultural reconstruction, as the distribution of the "oak" meaning in western branches has been used (controversially) to argue for a European homeland.

Notes

gsc-gap: source of "tree", "durable", "druid", "dendrite", "dryad", "tray"

Laryngeal Analysis

No laryngeal.

Ablaut

Static noun; nominative *dóru, genitive *dreus.