When something is so intensely something, it is literally THE ONLY thing of it's kind in specific genre. Can be good, bad or indifferent.
I have THE ONLY headache.

I have to take THE ONLY piss.

She has THE ONLY eyes, dude.
by Faith Alana Alastair February 25, 2009
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A retort that means, "What you've just said is plainly not true, although I certainly wish it were."
"I'm never going to call or e-mail you again." "If only!"

"Aren't you worried about the Republicans? Once they get into office, they'll reduce the size of government." "If only!"
by Doctor Whom July 15, 2005
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biggest, coolest, most important, worst, any extremety.
"we were making brownies and we made the only mess."
by ghettodawg2 August 07, 2007
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A term used by mathematicians and logicians to indicate that something happens under very specific conditions. Often seen in proofs and theories.
1) The sum a geometric sequence is given by a/(1-r) if and only if |r| < 1.

2) In a bar:
dumped guy: "My girlfriend left me because I told her I loved her!"
other guy: "What a bitch!"
dumped guy: "No, it's all my fault, she's a mathematician, and I should have said 'I love you and only you'".
by berkanator August 26, 2005
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it can be used to mean i wish this would happen. or it can also be used as a phrase rto mean maybe if this happens then....
person1: if only i were queen of the world.
person2: if only i was older than maybe he'd like me.
by purpleanjyl August 18, 2005
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Definition of onliness

plural -es

: the quality or state of being the only one working of an indicated or implied kind or category <was the only person and was lonely in his onliness>
I looked around and said damn I am the oldest and onliness working out here....
by onliness January 12, 2017
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One person, alone, who enjoys one other persons talents enough to want to form a friendship, or relationship, with them.

When plural, may be used as groupie, for supporting a group, or supporting AS a group.
W:I think you are my groupie.
J: I am not a group, and neither are you.
W: Well, no. So what are you then?
J: I'm an only.
by JDiebold August 28, 2007
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