noun

• The digit/figure 5.
• A banknote with a denomination of five units of currency. See also fiver.
• Anything measuring five units, as length.
• A person who is five years old.
• Five o'clock.
• A short rest, especially one of five minutes.
• (basketball) A basketball team, club or lineup.
• (UK) Abbreviation of MI5. [The domestic intelligence and counter-espionage agency of the United Kingdom, which operates in secret and whose primary function is to spy on terrorist organizations and others viewed as a threat to British national security. Formally known as the Security Service.]