wood (n.) Look up wood at Dictionary.com
Old English wudu, earlier widu "tree, trees collectively, forest, grove; the substance of which trees are made," from Proto-Germanic *widu- (cognates: Old Norse viðr, Danish and Swedish ved "tree, wood," Old High German witu "wood"), from PIE *widhu- "tree, wood" (cognates: Welsh gwydd "trees," Gaelic fiodh- "wood, timber," Old Irish fid "tree, wood"). Out of the woods "safe" is from 1792.
wood (adj.) Look up wood at Dictionary.com
"violently insane" (now obsolete), from Old English wod "mad, frenzied," from Proto-Germanic *woda- (cognates: Gothic woþs "possessed, mad," Old High German wuot "mad, madness," German wut "rage, fury"), from PIE *wet- (1) "to blow; inspire, spiritually arouse;" source of Latin vates "seer, poet," Old Irish faith "poet;" "with a common element of mental excitement" [Buck]. Compare Old English woþ "sound, melody, song," Old Norse oðr "poetry," and the god-name Odin.