Capable of being cracked, broken, or fractured; susceptible to breaking apart or forming cracks.
From 'crack' (Old English 'cracian' or from Old Norse influence) plus the suffix '-able' (from Old French '-able,' from Latin '-abilis'). '-able' means 'capable of' or 'susceptible to.'
The '-able' suffix is one of English's most productive—you can add it to almost any verb to create an adjective ('breakable,' 'fixable,' 'readable'), and it actually explains your word's meaning built into its structure.
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