intensifier
noun [ C ] language specialized uk/ɪnˈten.sɪ.faɪ.ər/ us/ɪnˈten.sə.faɪ.ɚ/ (also intensive)
（英语语法中的）强调成分（尤指副词或形容词）
a word, especially an adverb or adjective, that has little meaning itself but is used to add force to another adjective, verb, or adverb
In the phrases "an extremely large man" and "I strongly object", "extremely" and "strongly" are both intensifiers. 在 an extremely large man 和 I strongly object 中，extremely 和 strongly 都是强调成分。