The word "characterlessness" denotes a lack of distinctive features or individuality. Synonyms for this term include blandness, insipidity, insipidness, flatness, dullness, and unremarkableness. These words all convey a sense of mediocrity or lack of personality. Other synonyms for characterlessness might include anonymity, plainness, ordinariness, or nondescriptness. Essentially, any word that suggests a lack of distinction or uniqueness fits the bill as a synonym for characterlessness. It's worth noting that while few people would want to be described as characterless, there are plenty of situations-a hospital waiting room, for example-where being unremarkable might be preferable to standing out.