Hamadryads

n. king cobra of southeastern Asia and the East Indies, largest poisonous snake; (Greek and Roman mythology) tree nymph who lives in a tree and dies when the tree dies

Hamadryads are Greek mythological beings that live in trees. They are a specific species of dryad, which are a particular type of nymph. Hamadryads are born bonded to a specific tree. If their tree died, the hamadryad associated with it died as well. For that reason, dryads and the gods punished any mortals who harmed trees.
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Noun
1. the nymph or spirit of a particular tree
(hypernym) dryad, wood nymph
2. large cobra of southeastern Asia and the East Indies; the largest venomous snake; sometimes placed in genus Naja
(synonym) king cobra, Ophiophagus hannan, Naja hannah
(hypernym) cobra
(member-holonym) Ophiophagus, genus Ophiophagus

(pl. )
of Hamadryad
  

[Greek] Tree nymphs who lived and died with the tree they inhabited.