dryo-, dry- (Greek: oak tree; by extension, "tree").dryad: 
A forest nymph. 
 
Dryophyllum, dryophyllum: 
A genus of widely distributed, Upper Cretaceous and Tertiary trees supposed to be ancestors of modern oaks and beeches.
 Dryope: 
From a Greek myth, a playmate of the wood nymphs, beloved by Apollo. She was a daughter of king Dryops, eponymous ancestor of the Dryopes, or Dryopians, a Greek tribe originally of Thessaly.
 
Dryophyllum, dryophyllum: 
A genus of widely distributed, Upper Cretaceous and Tertiary trees supposed to be ancestors of modern oaks and beeches.
 
dryotomos: 
Woodcutter.
 
druid: 
An ancient Celtic priest or soothsayer. Compounded of daru-, dru, "oak", and wid-, "know"; hence literally meaning "they who know the oak"; so called with reference to their practices with mistletoe.
 
phellodrys: 
An evergreen oak.
 
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