Yoyo

[Sommer]

A toy consisting of a pair of joined discs with a deep groove between them in which string is attached and wound, which can be spun alternately downward and upward by its weight and momentum as the string unwinds and rewinds.

[Jessica]

Abbreviation for Youre On Your Own. Something you say after a stupid person says [YOLO], [letting] them [know that] you have no part in what stupid thing theyre about to do.

[Sonia]

Medical slang, but can be used anywhere: Means: Youre on your own. Used in a hospital on the day of discharge as in the phrase [OOB],[OTD], YOYO : Out of Bed, Out the Door, Youre on your own. Can be used by parents of [colleged] aged kids, or by someone breaking up with someone else. .

[Dianne]

Youre On [Your Own]

[Donald Trump]

[Stands] for: Your only [young] once.

[Michiko]

Youre Only Young Once
YOYO is a motivational phrase that nourishes the pursuit of happiness [in young] people. Unlike similar abused phrases, such as YOLO, YOYO remains positive and is seldom used by prepubescent girls [who seek] an excuse to expose their chest or by idiots who need a catchphrase for their Jackass-like stunts.
But theres much more to YOYO...
YOYO is not merely a term. Its a way of thinking. Its a state of mind. The basic principle of YOYO states that the journey, not the destination, is what permeates us with happiness. Thus, the start of the journey, the beginning of our life is of vital importance. The end could be anything. The end could be a slow, painful, [lung cancer]... or a sudden [plane crash]. Ergo, the most rational course of action is to give more importance to our youth and not the end.

[Mark Zuckerberg]

A [vagina] [looks like] a YoYo when viewed [from behind].

[Luis Fok]

Yo-Yo: A term used to describe the [sponging] 10 - 14 year olds who [roam around] amusement arcades, accosting strangers for money. This is usually opened with the statement Yo, yo, gimme fifty pee.
[Yo-Yos] are usually sent packing with a little verbal assault (or physical assault - its all good in this situation).

[Julian]

A) A greeting to friends that substitutes hi
A toy, usually a [circular] object on a string that people took [too far] and have tournaments over. Actually spelled [yo-yo]
C) A sarcastic expression of you trying to be ghetto