妈妈

Why does 妈妈 look like this?

This character is a 'phono-semantic' compound. On the left, we have 女 (nǚ), the 'Woman' radical, which tells us the meaning is related to a female. On the right, we have 马 (mǎ), which means 'Horse.' In this case, the horse doesn't provide the meaning but instead gives the character its sound (ma). Put them together and you get a warm, phonetic way to say Mother!