The characters combine vividly and literally to mean a “woman who worships gold/money.” The use of 拜 (bài) is key, as it elevates the desire for money from a simple preference to an act of worship, which is why the term is so powerfully critical.
The term 拜金女 rose to prominence alongside China's rapid economic growth over the last few decades. As a new class of wealthy individuals emerged and the wealth gap widened, societal anxieties about materialism, love, and marriage grew. 拜金女 became a label to describe a perceived social phenomenon. It's often used in public discourse to debate changing social values. On one hand, it's a harsh criticism of perceived greed and the erosion of traditional romantic values. On the other hand, some argue that the “拜金女 phenomenon” is a rational response to immense societal pressure on women to achieve security through marriage (“嫁得好” - jià de hǎo, “to marry well”) in a hyper-competitive environment.
拜金女 is an informal and highly derogatory term. It's almost always used to express disapproval or to insult someone.