Stout-stemmed is a term used to describe plants or trees with sturdy and thick stems. However, there are numerous synonyms that can be used to describe an object or organism with strong, thick, and robust stems. These synonyms include sturdy, robust, muscular, brawny, solid, tough, durable, powerful, and strong. These words can be used interchangeably depending on the context of the sentence, and they all have slightly different connotations. For instance, robust may imply a certain resilience, while powerful may suggest a greater degree of strength. All in all, these synonyms allow us to convey the same meaning without sounding repetitive.