conversible

adjective2

1. •
   (no longer used) Capable of being converted.

   • “But what do you call right? What’s your canon of certainty there?” “The conscience that’s in us—that charming, conversible, infinite thing, the intensest thing we know. […]” — 1889
2. •
   (no longer used) Capable of being substituted or swapped (with another thing).

   • Reciprocal signs I call those that are conversible with the thing they are the signs of. — 1683