Capable of being heated; able to have heat applied to it.
From 'heat' (Old English 'hæte') + '-able' (Latin '-abilis' meaning capable of). A straightforward modern formation using productive English suffixing.
Seemingly simple '-able' words are actually quite technical when you think about them: 'heatable' implies certain material properties—not everything can be heated evenly or safely. Engineers use this word to classify materials by their thermal properties.
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