十一号

Traditional (Taiwan): 十一號

shíyīhào ㄕˊ ㄧ ㄏㄠˋ

    • legs (humorous)
    • to walk (humorous)

Character by character

Saying俗语俗語

Idiom惯用语 · Widely known

Literally
number eleven
Meaning
Humorous slang for a person's two legs, since the numeral 11 looks like a pair of legs. Typically 'go by number eleven', meaning to walk.

Sources