The phrase "in a glow" means to be full of warmth, happiness, or excitement. Synonyms for this phrase include radiant, beaming, glowing, shining, euphoric, elated, thrilled, exhilarated, and enthusiastic. When someone is in a state of joy, they may be described as having a radiant smile, a beaming expression, or a glowing aura. Similarly, when someone is excited or thrilled about something, they may appear euphoric or elated. These synonyms can be used interchangeably depending on the context and the level of intensity of the emotional state. Overall, they all describe the feeling of being gleeful and satisfied.