“milk” in Japanese is 乳, read nyuu, chi (にゅう, ち). It is a Grade 6 Kyōiku kanji, taught in year 6 of Japanese elementary school, and appears in words such as 牛乳 (cow's milk).
What does 乳 mean?
赤ちゃんが牛乳を飲む。
Same sound, different character — the classic trap. Compare them side by side: