The term can refer to any of irradiance, luminous intensity, radiant intensity, or radiance, depending on the background of the person using the term.
ðə tˈɜːm kæn ɹᵻfˈɜː tʊ ˌɛni ʌv ˈɪɹeɪdˌiəns, lˈuːmɪnəs ɪntˈɛnsᵻɾi, ɹˈeɪdiənt ɪntˈɛnsᵻɾi, ɔːɹ ɹˈeɪdiəns, dᵻpˈɛndɪŋ ɔnðə bˈækɡɹaʊnd ʌvðə pˈɜːsən jˈuːzɪŋ ðə tˈɜːm.