Thirty can describe a thing, showing it has thirty parts or costs thirty of something. It helps tell quantity before a noun.
She bought a thirty dollar dress.
The thirty students are in the room.
Sometimes people say 'thirty' to mean thirty minutes of time. It's used in casual talk to say half an hour.
I will be there in thirty.
Can you wait for thirty before we start?
In military talk, 'thirty' means a gun or bullet that is 0.30 inches wide. It is short for 'thirty caliber.'
The soldier used a thirty to aim carefully.
They clean their thirty every day after practice.
'Thirty' is often used with verbs like 'turn' to talk about age. It means someone is becoming 30 years old.
He is turning thirty next week.
She will be thirty in two months.
In some card games, thirty means a score or points level. Players use it to say how many points someone has.
He reached thirty in the card game.
The score is thirty to fifteen now.
In radio talk, especially in the police or military, 'thirty' means that a message or assignment is complete. It is a shorthand code.
"Unit seven to base, we are thirty."
"Thirty on that task, moving to next."
