In voice procedure (the techniques used to facilitate spoken communication over two-way radios) a station may request a report on the quality and strength of signal they are broadcasting. In the military of the NATO countries, and other organizations, the signal quality is reported on two scales; the first is for signal strength, and the second for signal clarity. Both these scales range from one to five, where one is the worst and five is the best. The listening station reports these numbers separated with the word "by". Five by five therefore means a signal that has excellent strength and perfect clarity -- the most understandable signal possible.

Five by five by extension has come to mean "I understand you perfectly" in situations other than radio communication, the way Loud and Clear entered slang, post-WW2.

It is sometimes used as slang term to mean "everything is good". The character "Faith" from the "Buffy The Vampire" TV series used it this way.

Sometimes also used in athletic training.
A radio operator would ask: "Radio check -- how am I coming in?" A responder could say; "You are coming in 5 x 5 (5 by 5)". (This means that your signal strength and clarity are both 5 out of a 1-5 scale, where 5 is the best strength and clarity.)

Or, as slang:
A person would ask; "How are you doing?" The responder could say; "I'm 5 x 5." (5 by 5, meaning I'm doing/feeling great.)
by phreich May 1, 2010
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On track, on course, going where you want to; it also refers to the central point in a targeting scope - five over and five up.
We're on course, 5 x 5.

I've got him in my sights, 5 x 5.
Take him out.
by J Fieth February 23, 2008
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If you are "all square" with someone (as opposed to being just a square), or you are cool with that person, then you are 5 x 5.
We talked through our differences, so now we are 5 x 5.
by socrates+ January 28, 2006
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To get at least 5 in each of the major stat categories in a basketball game; points, rebounds, assists, blocks, and steals.
AK-47 is known for getting 5 x 5's.
by WhiteJordan April 4, 2006
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A state of being, discribes level of mood, use widely in chat rooms and online slang.
5 x 5 = not in a bad mood, and, not in the greatest mood.
5 x 5 = things are just fine, not to bad
by tommynepa January 26, 2006
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