Capable of being closed; able to be shut or sealed with a fastening.
From 'close' plus the suffix '-eable,' an alternate spelling of '-able.' Both 'closable' and 'closeable' are equally valid modern English, though '-able' is more common.
The existence of both 'closable' and 'closeable' is a perfect example of English's messiness—we have two correct spellings, and dictionaries have basically said 'pick whatever sounds better to you'!
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