The antonym for the word "more rubbery" is "less rubbery". Rubberiness can be described as the degree of elasticity, flexibility or malleability of a material. The less rubbery a material is, the more brittle or rigid it becomes. Some of the antonyms for "more rubbery" can be words such as hard, tough, inflexible, or stiff. Factors that can affect the rubberiness of a material include temperature, pressure, and composition. For example, a high concentration of fillers, such as carbon black, can make a rubber compound stiffer and less rubbery. Understanding antonyms and synonyms can help to improve one's vocabulary, communication skills, and overall language proficiency.