A chemical or pharmaceutical agent related to light-reactive compounds or substances with light-related properties.
From Latin 'ad-' (to) combined with 'lumen' (light). This appears to be a technical or scientific term, possibly obsolete or specialized in particular fields.
The Latin root 'lumen' (light) built entire scientific vocabularies—'adlumin' compounds show how scientists keep reaching back to Latin to name things that interact with light, from photography to fiber optics.
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