The word "bellered" is a vivid and highly specific term, often used to describe the loud, deep roar of a large animal. However, if you're looking for synonyms to use in your writing, there are a few options that may be more versatile and widely understood. You could use "roared" to describe any loud, powerful sound, or "bellowed" to suggest a deeper, more resonant quality. "Shouted" or "yelled" could also convey a similar sense of intensity and volume, albeit without the animalistic connotations. Ultimately, it's up to you to choose the word that best reflects the tone and imagery you're trying to create, but these options are a good place to start.