oh dark thirty

A non-specific time in the early morning before the sun has risen. Based on the way in which military time is said aloud. ("Oh" is a common way of saying the number 0.) Why on earth are we meeting at oh dark thirty? The only thing we should be doing at this hour is sleeping! We'll have to leave at oh dark thirty if we want to reach Las Cruces before sundown.

thirty pieces of silver

The amount Judas Iscariot was paid to betray Jesus Christ, used figuratively as a symbol of treachery or treason. She carried the guilt with her for the rest of her life after turning her husband over to the mob, and the money she made from it—her thirty pieces of silver—became utterly loathsome to her.

thirty-something

1. adjective Of an unspecified age in one's thirties. He looks like he's in his 50s, but he's really just thirty-something.

2. noun A person who is in their thirties. Usually used in the plural. With so many college students in this town, it's nice to find a place that's geared more for thirty-somethings.

zero dark thirty

A non-specific time in the early morning before the sun has risen. Based on the way in which military time is said aloud. Why on earth are we meeting at zero dark thirty? The only thing we should be doing at this hour is sleeping! We'll have to leave at zero dark thirty if we want to reach Las Cruces before sundown.

thirty-something (or forty-something, etc.)

an unspecified age between thirty and forty (forty and fifty, etc.). informal

thirty pieces of silver

The symbol of treason. This term comes from the Bible, where Judas’s price for betraying Jesus was thirty pieces of silver (Matthew 26:15). It has symbolized betrayal ever since.