女友指浪漫或性关系（romantic/sexual relationship）中相对稳定（regular）的女性伙伴，但通常不属于长期承诺性的关系（long-term committed relationship），这种情况需要用妻子（wife）或爱侣（partner）的说法。
1. Girlfriend也可以简称girl
特别随意的场合可以用gf或GF，如短信（texting）或网聊（internet chat）。
eg: Have you been seeing a guy pretty steadily and would like to know if he wants you to be his girlfriend?
2. 非婚关系中，口语通常可称女方为significant other或SO
这个词不突出性别，只强调亲密关系，所以也可用于男方。类似汉语的‘另一半儿’、‘那口子’、‘他那位’等，但不透露或假设婚姻状态或性取向，用于故意模糊以避免冒犯别人。
eg: Anyone NOT having their Significant Other in the Delivery Room?
3. Life partner通常相当于‘终身伴侣’
但与汉语不同的是它也可以指亲密的终身伙伴，无论同性还是异性。Partner也可以指life partner。
eg: I feel more optimistic being in this relationship. We decided we are going to be life partners.
4. Soulmate或soul mate可以指女友或妻子
也可以指未必有亲密关系的精神伴侣，有一定的神秘或宗教意味。另外，mate也可以指女友。这几个词不区分性别。
eg: So did "God" give attractive people a much higher chance of meeting their soulmate?
5. Fiancée指订婚女友
相对概念是fiancé，及订婚男友。
eg: A 45-year-old man and his fiancée were celebrating a family holiday in their apartment. Out of the blue the man thought that his girlfriend was taking the form of a hideous monster from a horror movie.
6. 有一些词是男女通用的，如true love、date、steady、darling、love、lover、paramour、squeeze等。
7. 还有其它一些词可以指女友，如companion、sweetheart、heartthrob、babe等。
8. 如果是已婚男人的情人，通常用mistress
eg: Picasso’s painting of his mistress will go under the hammer at London
9. Lady friend是个故意模棱两可的用语
指关系不到girlfriend的程度，但却好于friend；没有mistress或lover那种明显的性意味。通常作为委婉语（euphemism）使用，或者在情况不明的情况下作为一种保守的提法。Lady friend也用于指女方明显大于男方的情侣关系。
eg: A millionaire took his lady friend to dinner. He told her he had eaten in the finest restaurants in the world and assured her this place served the best.
10. girl friend或female friend
没有浪漫关系（non-romantic）或性关系的（non-sexual）女性朋友可用girl friend或female friend一词。Girl friend和girlfriend也有所不同，前者可用于指一般女性朋友。
eg: The fine line between girl friends and girlfriends lies in sexual attraction and flirting.
