Английский Этимологический словарь - tree

- O.E. treo, treow "tree" (also "wood"), from P.Gmc. *trewan, from PIE *deru-/*doru- "oak." Importance of the oak in mythology is reflected in the recurring use of words for "oak" to mean "tree" (cf. Skt. dru, Rus. drevo). In O.E. and M.E., also "thing made of wood," especially the cross of the Crucifixion and a gallows (cf. Tyburn tree, gallows mentioned 12c. at Tyburn, at junction of Oxford Street and Edgware Road, place of public execution for Middlesex until 1783). Sense in family tree first attested 1706; verb meaning "to chase up a tree" is from 1700. Tree-hugger, contemptuous for "environmentalist" is from late 1980s.