Example sentences
niú牛nǎi奶zài在bīng冰xiāng箱lǐ里。
The milk is in the fridge.
zǎo早shàng上hē喝bēi杯niú牛nǎi奶。
Have a glass of milk in the morning.
About this word
牛 is "cow" and 奶 is "milk", so 牛奶 is cow's milk, the default milk in a Chinese shop. Chinese builds food words by naming the animal first, the same pattern as 鸡蛋, 羊肉 and 猪肉. Once you know 奶, a whole shelf opens up: 酸奶 (yoghurt, "sour milk"), 奶茶 (milk tea), 奶粉 (milk powder), and 奶奶, where the syllable doubled makes "grandmother". On its own 奶 can mean milk in general, and as a verb it means to nurse a baby.
The story behind the character
牛
牛 is a bull's head seen from the front. Two horns curving up, the face below, drawn in three or four strokes. You can still find that shape in the oracle bones. Xu Shen called 牛 大牲也, the great sacrificial animal, which is what cattle mostly were to the Shang court.
奶
奶 is 女 (woman) with 乃 on the right giving the sound. It is a young character, not in Xu Shen's dictionary; the older form was 嬭. The word started in the world of nursing and minding small children, and ended up as plain milk. 牛奶 is 牛 plus 奶, cow plus milk, with no decoration at all.