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Related to thirty: Thirty Years War

oh dark thirty

In military time, a non-specific time in the early morning, before the sun rises. Why on earth are we meeting at oh dark thirty? That's too early to do anything besides sleep!
See also: dark, oh, thirty


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.

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.
See also: of, piece, silver, thirty
References in classic literature ?
I would replace the destroyed instruments upon the bridge; every officer and man should know when we crossed thirty.
I knew that I was a good officer and sailor, and I didn't propose submitting to degradation and discharge because a lot of old, preglacial fossils had declared over two hundred years before that no man should cross thirty.
Johnson, I intend retaining command of the ship, even though she crosses thirty, and I shall demand implicit obedience from every officer and man aboard until I am properly relieved from duty by a superior officer in the port of New York.
You mean to say that you will cross thirty without submitting to arrest?
His face brightened at my words, and he assured me that I would find him as ready to acknowledge my command upon the wrong side of thirty as upon the right, an assurance which I hastened to tell him I did not need.
The storm continued to rage for three days, and as far as the wind scarce varied a point during all that time, I knew that we must be far beyond thirty, drifting rapidly east by south.
The crew had known almost as soon as I that we were doomed to cross thirty, and I am inclined to believe that every man jack of them was tickled to death, for the spirits of adventure and romance still live in the hearts of men of the twenty-second century, even though there be little for them to feed upon between thirty and one hundred seventy-five.
They might cross thirty with impunity, and doubtless they would return to be heroes at home; but how different the home-coming of their commanding officer!
Islamabad thirty-two degree centigrade, Lahore thirty-five, Karachi thirty, Peshawar thirty-three, Quetta and Gilgit nineteen, Murree twenty-two and Muzaffarabad twenty-one degree centigrade.
Synopsis: Written from the experienced viewpoint of skilled artist Andrew Jay Svedlow, "Thirty Works of Art Every Student Should Know" examines thirty pieces of world-renown artwork, each of which representing a different style and movement from the vast history of art.
com)-- Cupsogue Pictures are pleased to announce that it has signed to produce romantic-comedy 'Twenty Thirty Forty' written by Graham V Rushton.
A smart start from red, assisted by a missed break from Thirty By Thirty in two, gave the April 09 whelp a dream run into the first bend and he was then able to quicken clear down the far side.
Prime Minister Saad al-Hariri said at the end of his talks in Moscow last month that Russia had decided to donate to the Lebanese army six helicopters model MI 24, thirty one tanks model T-72, thirty six 130 mm canons, about half a million munitions for various weapons and thirty thousand artillery shells for the 130 mm canons.
FAST on their way to becoming one of the world's biggest bands, Thirty Seconds To Mars have announced a gig at the Metro Radio Arena in Newcastle.
PESHAWAR, December 04, 2009 (Balochistan Times): Thirty inspectors have been promoted on post of DSP while the decision of promotions has been made in light of recommendations of Frontier police.