Adjective brittle has 3 senses
- brittle, brickle, brickly - having little elasticity; hence easily cracked or fractured or snapped; "brittle bones"; "glass is brittle"; "`brickle' and `brickly' are dialectal"
Antonym:  unbreakable (indirect, via breakable)
 - brittle - lacking warmth and generosity of spirit; "a brittle and calculating woman"
Antonym:  warmhearted (indirect, via coldhearted)
 - brittle, unannealed - (of metal or glass) not annealed and consequently easily cracked or fractured
Antonyms:  tempered, treated, hardened, toughened (indirect, via untempered)
 
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Noun brittle has 1 sense
- brittle, toffee, toffy - caramelized sugar cooled in thin sheets
--1 is a kind of candy
--1 has particulars: peanut brittle
 
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