Capable of being added or combined with something else; suitable for addition.
From Latin addere (to add) plus Germanic suffix '-ible' (capable of). The word emphasizes the potential for combining things mathematically or conceptually.
While 'addible' is rare today, mathematicians actually need this word—not all things are 'addible' (you can add numbers but not necessarily colors in the same way, until you invent a system that lets you).
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