Synonyms for Ultraviolet (same or very similar meaning)
WordNet sense 1 (radiation lying in the ultraviolet range; wave lengths shorter than light but longer than X rays):
UV, ultraviolet illumination, ultraviolet light, ultraviolet radiation
WordNet sense 2 (impossible or nearly impossible to see; imperceptible by the eye):
invisible, unseeable
From the ODE community, based on WordNet
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