The number 5 (五wŭ) is associated with the five elements (Water, Fire, Earth, Wood, and Metal) in Chinese philosophy, and in turn was historically associated with the Emperor of China. For example, the Tiananmen gate, being the main thoroughfare to the Forbidden City, has five arches. It is also referred to as the pronoun "I"[citation needed], as the pronunciations of"I" (我wŏ, or 吾wú) and 5 are similar in Mandarin.

In Cantonese, this word has the same pronunciation as the character 唔and means "not", pronounces (m̀h). This word has the same meaning and use as the word 不an therefore is usually negative.