Capable of being criticized; open to criticism or objections.
From criticise (British spelling of criticize, from critic) plus -able suffix meaning 'capable of.' British English prefers this -s- spelling while American English uses -z-.
The -able suffix is so productive in English that you can slap it onto almost any verb: criticise, criticisable; critique, critiqueable. It's like English has a built-in word-generation machine.
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