ㄨ = u
ㄨ is a medial. It can stand alone, or link an initial to a final. In pinyin it is written u.
Pinyin uIPA /u/Medial · Medials2 strokesFrom 㐅

How to say it
Round the lips: “oo” as in “food”.
Do not mix up
ㄨ is a plain “oo”; ㄩ is “ee” with rounded lips. See ㄩ (ü) →
Where it comes from
ㄨ comes from the character 㐅, an old form of 五 (five). Zhuyin symbols were made from parts of old characters in the 1910s.
Stroke order, step by step
Stroke order from Taiwan’s Ministry of Education. The dot shows where the new stroke starts.
Words with ㄨ
五
ㄨˇ
wǔ · five; 5 · TOCFL Novice 1
珍珠
ㄓㄣ ㄓㄨ
zhēn zhū · Pearl
注音
ㄓㄨˋ ㄧㄣ
zhù yīn · Bopomofo; Zhuyin
我的
ㄨㄛˇ ˙ㄉㄜ
wǒ de · my; mine
桌子
ㄓㄨㄛ ˙ㄗ
zhuō zi · table; desk
烏
ㄨ
wū · crow; black
98 syllables with ㄨ
ㄅㄨbuㄆㄨpuㄇㄨmuㄈㄨfuㄉㄨduㄉㄨㄛduoㄉㄨㄟduiㄉㄨㄢduanㄉㄨㄣdunㄉㄨㄥdongㄊㄨtuㄊㄨㄛtuoㄊㄨㄟtuiㄊㄨㄢtuanㄊㄨㄣtunㄊㄨㄥtongㄋㄨnuㄋㄨㄛnuoㄋㄨㄥnongㄌㄨluㄌㄨㄛluoㄌㄨㄢluanㄌㄨㄣlunㄌㄨㄥlongㄍㄨguㄍㄨㄚguaㄍㄨㄛguoㄍㄨㄞguaiㄍㄨㄟguiㄍㄨㄢguanㄍㄨㄣgunㄍㄨㄤguangㄍㄨㄥgongㄎㄨkuㄎㄨㄚkuaㄎㄨㄛkuoㄎㄨㄞkuaiㄎㄨㄟkuiㄎㄨㄢkuanㄎㄨㄣkunㄎㄨㄤkuangㄎㄨㄥkongㄏㄨhuㄏㄨㄚhuaㄏㄨㄛhuoㄏㄨㄞhuaiㄏㄨㄟhuiㄏㄨㄢhuanㄏㄨㄣhunㄏㄨㄤhuangㄏㄨㄥhongㄓㄨzhuㄓㄨㄛzhuoㄓㄨㄢzhuanㄓㄨㄣzhunㄓㄨㄤzhuangㄓㄨㄥzhongㄔㄨchuㄔㄨㄟchuiㄔㄨㄢchuanㄔㄨㄣchunㄔㄨㄤchuangㄔㄨㄥchongㄕㄨshuㄕㄨㄚshuaㄕㄨㄞshuaiㄕㄨㄟshuiㄕㄨㄣshunㄖㄨruㄖㄨㄛruoㄖㄨㄟruiㄖㄨㄢruanㄖㄨㄣrunㄖㄨㄥrongㄗㄨzuㄗㄨㄛzuoㄗㄨㄟzuiㄗㄨㄣzunㄗㄨㄥzongㄘㄨcuㄘㄨㄛcuoㄘㄨㄟcuiㄘㄨㄣcunㄘㄨㄥcongㄙㄨsuㄙㄨㄛsuoㄙㄨㄟsuiㄙㄨㄢsuanㄙㄨㄣsunㄙㄨㄥsongㄨwuㄨㄚwaㄨㄛwoㄨㄞwaiㄨㄟweiㄨㄢwanㄨㄣwenㄨㄤwang
Make ㄨ glow.
Zhuyin Pro teaches ㄨ with sound, mouth diagrams, tracing and real words. Then it reminds you before you forget.
Get it onGoogle Play