Capable of being hewn or cut with an axe or similar tool.
From 'hew' plus the suffix '-able' (from Latin 'habilis' meaning 'fit' or 'suitable'). This is a regular formation in English where '-able' transforms verbs into adjectives describing potential action.
The '-able' suffix is one of English's most productive word-building tools—you can theoretically add it to almost any verb (cookable, spreadable, fixable), which is why dictionaries struggle to include every possible variant.
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