Where does the term "waifu" come from? I was stalking a forum looking for images to nab to use as wallpapers, and there was a post where posters were claiming characters as their "waifu".

Seeing how it is spelled, I would assume that what they mean is "wife"; however, it seems weird to use the term "waifu" rather than the normal Japanese term for wife (my understanding is that it's "Tsuma" (妻); however, I could be wrong).

So, where did the term "waifu" come from? If I am wrong, and "waifu" isn't what I think it is, could someone explain what it is and where it came from?
Origin
The prevailing wisdom1 is that the term &quot;waifu&quot; originates from a scene from the 2002 anime Azumanga Daioh; specifically, this scene from episode 15.
Some context: the male character in that scene, Mr. Kimura, is a teacher at the school the female characters in that scene attend. Mr. Kimura has a well-deserved reputation for being generally perverse and possibly a pedophile.
A rough translation of the scene follows:

TAKINO Tomo: What's this? A picture of a woman?
KASUGA Ayumu: Wow, she's beautiful.
TAKINO Tomo: Who is she?
KIMURA: My wife.
All: That can't be!

The astute listener will observe that Kimura uses the English words &quot;my wife&quot;, rather than a Japanese translation thereof (such as 妻2 tsuma). When the words &quot;my wife&quot; are adapted to conform to Japanese phonological constraints (e.g. no terminal /f/), and then re-expressed in a Japanese syllabary (hiragana/katakana), the result is マイワイフ. Finally, when we romanize マイワイフ, we get &quot;mai waifu&quot;.
Usage
The below graph shows that usage of &quot;waifu&quot; on the internet was effectively negligible until early 2007. This seems to suggest that &quot;waifu&quot; did not become memetic until some time after Azumanga Daioh aired.

There is evidence from the Animesuki forums that &quot;waifu&quot; (in fact, &quot;mai waifu&quot;) was being used in its modern sense (rather than the literal standard-English &quot;woman one is married to&quot; sense) by May 2006. Interestingly, this appears to precede the rise in searches for &quot;waifu&quot; on Google Trends. I'm not sure what this means, but it probably means something.
Husbandos
There is also a male counterpart to &quot;waifu&quot;: husbando. Unlike &quot;waifu&quot;, &quot;husbando&quot; is not derived from Japanese3. Rather, it was developed by analogy, as an idealization of how a Japanese speaker might pronounce the word &quot;husband&quot;. A &quot;husbando&quot; is basically the same thing as a &quot;waifu&quot;, except male rather than female.
The earliest citation I've found for &quot;husbando&quot; is from October 2007 (again, on Animesuki). With some internet archaeology, I suspect it should be possible to show that usage of &quot;husbando&quot; began as much as a year prior to this citation.

Notes
1 I say that this is the prevailing wisdom, because I have no evidence that &quot;waifu&quot; was not used prior to 2002.
2 The Japanese equivalent of &quot;mai waifu&quot;, in terms of usage among otaku and memeticity and so forth, is actually 俺の嫁 (&quot;ore no yome&quot;, lit. &quot;my bride&quot;).
3 ハズバンド hazubando exists, but I'm almost certain this didn't directly give rise to English &quot;husbando&quot;. At most, it may have been an inspiration.