他那双深邃的眼睛有一种令人着迷的魔力。

His deep eyes had a mesmeric quality that was hard to resist.

mesmeric 是由名词 mesmer（催眠术）加上形容词后缀 -ic 构成的形容词。mesmer 来自奥地利医生 Franz Mesmer 的名字，他创立了动物磁力学说（mesmerism），即早期的催眠术理论。因此 mesmeric 字面意思是"催眠术般的"，引申为"令人着迷的、有魔力的"。