猫咪是一种温顺可爱的动物，因此在互联网上，许多人都喜欢在自己的网名中加入“猫”字，以表达自己的可爱和温柔。以下是一些含有猫字的网名所表达的可爱和温柔情感的英文描述。

1. MeowMeow: This cute and playful name is perfect for someone who loves cats and enjoys being playful and fun-loving.

2. KittyKat: This name is perfect for someone who is sweet and affectionate, like a cuddly kitten.

3. CatLady: This name is perfect for someone who loves cats and enjoys spending time with them. It suggests a warm and nurturing personality.

4. Purrfect: This name suggests someone who is confident and comfortable in their own skin, like a cat who is perfectly content with itself.

5. FelineFine: This name suggests someone who is elegant and refined, like a sleek and graceful cat.

6. WhiskerWonder: This name suggests someone who is curious and adventurous, like a cat exploring its surroundings.

7. ClawedCompanion: This name suggests someone who is loyal and protective, like a cat who will defend its owner fiercely.

In conclusion, adding the word 'cat' to a username can add a touch of cuteness and playfulness, as well as suggest certain personality traits like affection, warmth, confidence, elegance, curiosity, loyalty, and protectiveness.