From geisli (“beam, ray”) + -a (“suffix used to form verbs from nouns”). geisla (weak verb, third-person singular past indicative geislaði, supine geislað)...
From geisla (“to radiate”) + -un. geislun f (genitive singular geislunar, no plural) radiation “geislun” in the Dictionary of Modern Icelandic (in Icelandic)...
geisli. IPA(key): /ˈceistlɪ/ Rhymes: -eistlɪ geisli m (genitive singular geisla, nominative plural geislar) beam, ray (of light, radio waves, showing control...