What is meant by unchastity is the taint in a woman?

Women who know only one man sexually and have a reasonably moral husband will instinctually, for the most part, remain fiercely loyal & bonded to that man & particularly to their family. This is why virginity is cherished in basically every major religion and this is why sexual misconduct either by a woman or towards a woman taints a woman. Her natural instinctual bonding can be lost; which also explains why in our current era of sexual liberalism there are so many struggles by women (and men) in maintaining relationships; why so many women are hungry ghosts; why so many women are using antidepressants; and why so many women crucify a man in divorce out of revenge.

AN 6.52 states:

Women have a man as their ambition. They explore for adornments. They’re committed to their children. They insist on being without a co-wife. Their ultimate goal is domination.

I realize that this text is translated, therefore, this may not be an accurate comment, but I respectfully suggest that in the text the woman is passive to the misconduct (receives it), but in the comments/answers you are assuming she is perpetrating it. In some cultures a woman who is adulterous is still the passive person because she "received" the advances of the other man. There is also nothing to make clear if she was willing in the story. The man may be distraught because she was assaulted and he failed to protect his wife. (he is ashamed in the story, not angry with her).

This is what I mean: "He engages in sensual misconduct." the man is the actor of the misconduct

"1) Non-recitation is the stain of the hymns." the hymns are stained by not being recited, they are not active in their own "stain" but the inaction of others makes them stained.

"(2) The stain of houses is lack of upkeep." here the house which is not maintained is stained by the inattention of others. It is passive to the action.

"(3) The stain of beauty is laziness." again, same, the beauty which would shine is diminished (stained) by others not expressing/creating it.

"(4) Heedlessness is the stain of a guard." this is a little less clear. When I take the definition of heedlessness as ( adjective. 1. careless; thoughtless; unmindful: Heedless of the danger, he returned to the burning building to save his dog.) I can see that a guard put in unnecessary danger by others or that he may be careless. Both are valid to the text as translated.

"(5) A woman’s stain is misconduct." she is stained by the misconduct, but it does not say if she is the doer, or someone does to her this misconduct. It could be completed as a woman's stain is a man's misconduct or a woman's stain is the result of her own misconduct Perhaps it is both and that is why neither is specified.

"(6) Miserliness is a donor’s stain." it is unclear if it is his own miserliness (the limit to his generosity), the lack of other people's joining him, or his giving (he is a donor) without clean motivation.

"(7) Bad unwholesome qualities are stains in this world and the next." neither this world nor the next are the perpetrators of the unwholesome qualities, they are stained by the actions of others.

"(8) A stain graver than this is ignorance, the very worst of stains." if I understand it, this is a continuation of the 7th, that this world and the next are stained by the ignorance of others (not their own).

"My disciple, women are just like a river, or a road, or a liquor shop or a rest house, or a water-pot stand at the roadside; they associate with all sorts of people. Indeed, sexual misconduct is the cause of ruin for a woman."

all of the items listed (river, road, liquor shop, rest shop, water-pot stand) are objects, not perpetrators of the action. they are perhaps temptations, but not actors. Noticeable that none of them have the power to stop the person who associates with them (the water-pot-stand cannot turn away the thirsty passer-by)

IMO "woman's stain" is a mistranslation (or at best gives the wrong impression).

The whole chapter (of the Dhammapada) is about ways in which the audience (e.g. you or me) may be stained (or are stained, were stained).

(It would be applicable to "a woman" only if she were the reader, the subject, the audience of the talk -- but in the AN 8,15 context, at least, the audience was all men, all bhikkhus).

I think that (i.e. that it's the audience's stain, or that the audience would be stained if they were blame-worthy) is evident from the context -- for example from the start of that chapter of the Dhammapada:

239. One by one, little by little, moment by moment, a wise man should remove his own impurities, as a smith removes his dross from silver.

... through to the end ...

252. Easily seen is the fault of others, but one's own fault is difficult to see. Like chaff one winnows another's faults, but hides one's own, even as a crafty fowler hides behind sham branches.

253. He who seeks another's faults, who is ever censorious — his cankers grow. He is far from destruction of the cankers.

It's meant as advice to you ... and is not a statement that's meant to censure "a woman" (itthiyā).

Similarly you may be stained by ...

• Your being lazy in the presence of beauty
• Your having a house and being negligent (or, possibly, being negligent because you have a house)
• Your misconduct with a woman

The Pali (Malitthiyā duccaritaṃ or malaṃ itthiyā duccaritaṃ) doesn't have all the prepositions which translators add to the English (at most the Pali nouns are declined, have a case ... I think itthiyā is declined like jāti, for what that's worth, so the syntax doesn't distinguish whether it's genitive, locative, dative, ablative, or instrumental; there's no verb).

I think the word-order in the Dhammapada is unreliable (it's highly condensed, to make it verse); but that the word-order in AN 8.15 i.e.

malaṃ, bhikkhave, itthiyā duccaritaṃ

... implies that the word itthiyā is there to qualify the type of misconduct, and not there to be the agent, owner, or object of the stain.

I cross-posted this to SuttaCentral -- Questioning the translation of AN 8.15, “Misconduct is a woman’s stain”.

I also wrote there that I think that the translations (or at least the interpretations) of most of the other stains are questionable too.