Despite her initial resistance, she eventually succumbed to the desire to buy the expensive dress.

succumbed 是动词 succumb 的过去式，succumb 由前缀 suc-（表示"在...之下"）和词根 -cumb（来自拉丁语，意为"躺下"）组成，字面意思是"躺倒在...之下"，引申为"屈服、抵挡不住"。succumbed 在这里表示"最终没能抵抗住诱惑而屈服"。