Capable of being extended or stretched; able to expand in length or scope; relating to extension.
From Latin 'extensus' (stretched out) plus the suffix '-ible.' This is a rare variant or alternate spelling of 'extensible,' emphasizing the quality of being stretchable.
The word 'estensible' is basically obsolete English—it lost out to 'extensible'—but it shows how languages constantly prune unnecessary variations; you don't need two words when one does the job!
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