What is a group of Fireflies called?

A group of fireflies is commonly called a Swarm. Other collective nouns you may see include Cloud and Wheel.

A collective noun is a term used to describe a group of the same type of animals or things. In the case of fireflies, these mesmerizing insects, known for their luminous glow, are part of a captivating spectacle when seen in large groups. Whenever fireflies gather together, they form a collective noun that evokes the magical charm they bring to moonlit summer nights. One of the most frequently used collective nouns for fireflies is a "glow" of fireflies. This term perfectly captures their defining characteristic - the radiant light they emit. Imagine standing in a serene meadow, surrounded by countless fireflies illuminating the night, creating an enchanting visualization of twinkling lights in the dark. The delicate dance of these radiant insects emanates both fascination and serenity, as if their gentle flickering echoes the very rhythm of the night itself. In these moments, you may witness a "glow" of fireflies, as if suspended stars had come alive at your retreat, transforming the ordinary into the extraordinary. Another creative collective noun that sometimes appears is an "exaltation" of fireflies. This term illustrates the ethereal display put on by these small but extraordinary insects, symbolizing a profound sense of admiration and reverence. This portrayal paints a poetic picture of fireflies, causing their presence to be celebrated for the beauty they introduce to their surroundings. The "exaltation" alludes to feelings of transcendent wonderment as one watches the luminous display, where every insect becomes a participant in a grand performance of nature's magical theater. Whether we imagine a "glow" or an "exaltation," collective nouns for fireflies offer distinctive and vivid imagery, inviting us to marvel at the awe-inspiring elegance of these small creatures. The terms allow us to encapsulate the harmonious gathering of fireflies, their collective luminosity amplifying the enchantment and evoking an atmosphere of wonder and tranquility.