An annoying swarm can be described in many ways. Some synonyms for this phrase include irritating flock, vexing crowd, bothersome group, upsetting mass, exasperating gathering, and aggravating bunch. These terms all encompass the annoyance and discomfort that can come with a large group of individuals or creatures. Other synonyms that can be used to describe an annoying swarm include frustrating mob, maddening throng, irritating horde, and troublesome swarm. Regardless of the exact phrasing used, these synonyms all convey a sense of irritation and annoyance that can arise from a chaotic and overwhelming group of organisms.