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Synonyms for Brittle (same or very similar meaning)

WordNet sense 1 (caramelized sugar cooled in thin sheets):
toffee, toffy

WordNet sense 2 (lacking in sympathy or feeling):

WordNet sense 3 ((of metal or glass) not annealed and consequently easily cracked or fractured):

WordNet sense 4 (not brought to a proper consistency or hardness):
unhardened, untempered

WordNet sense 5 (having little elasticity; hence easily cracked or fractured or snapped):
brickle, brickly

WordNet sense 6 (capable of being broken or damaged):

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