This root form (lemma) is used in 2 different forms in the NT: φωστὴρ (NMS), φωστῆρες (NMP).
It is glossed in 2 different ways: ‘lights’, ‘radiance’.
OET PHP 2:15 Greek word=φωστῆρες (fōstaʸres) Morphology=NMP English gloss=‘lights’ SR GNT PHP 2:15 word 22
OET REV 21:11 Greek word=φωστὴρ (fōstaʸr) Morphology=NMS English gloss=‘radiance’ SR GNT REV 21:11 word 9