Capable of being frightened; susceptible to being scared or made afraid.
From 'frighten' plus the suffix '-able,' formed in the same way as 'frightable' but with the more common modern form of the root verb 'frighten.'
Both 'frightable' and 'frightenable' mean the same thing, but 'frightenable' uses the more modern verb form, showing how English gradually standardized around 'frighten' instead of 'fright' as a verb.
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