Able to be authorized, permitted, or given official approval (British spelling of 'authorizable').
From 'authorize' (via Old French from Latin 'auctorizare') plus the suffix '-able' (from Latin 'habilis' meaning 'able'). The British '-ise' spelling reflects different Anglophone conventions.
The existence of words like 'authorisable' shows how legal and bureaucratic language creates words for concepts that didn't really exist before formal governments—medieval people couldn't 'authorize' things in this official sense.
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