What's the adjective for injectivity? Here's the word you're looking for.
Included below are past participle and present participle forms for the
verb inject which may be used as adjectives within certain contexts.
injective
(mathematics) Of, relating to, or being an injection: such that each element of the image (or range) is associated with at most one element of the preimage (or domain); inverse-deterministic.
“However, a novel form of cutaneous anthrax, termed injectional anthrax, that is characterized by severe soft tissue infection has been recently described in heroin users.”