Sotah 6:1 talks about when a man who hears about his wife violating his warning divorces her rather than invoking the sotah test:
Someone who warned his wife [against being secluded with a certain man] and then she secluded herself [with him], even if he [her husband] heard from a fluttering bird, he divorces her and gives her the Ketubah [monetary settlement payable to a married woman upon divorce or the death of her husband]. These are the words of Rabbi Eliezer. Rabbi Yehoshua says, only when the women who twist yarn by the moon talk of her.
From context it's pretty clear that Rabbi Yehoshua is talking about the rumor mill -- when people start talking about the incident he has to act, but before then he can divorce her instead. But what a strange description of the rumor mill!
Who are the "women who twist (spin) yarn by the moon (moonlight)"? Was spinning at night a special, social thing, unlike spinning by day? I wouldn't expect women to commonly be out of the home at night, especially if there are young children to tend? (I'm aware of the monthly exception; I'm not talking about that.)
I believe that at the time, spinning wool into yarn was done with a hand-held device -- we're not talking about spinning wheels, which come much later. So it's portable, but I would still expect "portable spinning" to happen mostly by day. Were the "women who spin by the moon" a common occurrence, or was this an activity that would raise eyebrows to begin with?
In addition to the historical/societal curiosity, the two might be different standards of rumor-mills -- when people who already violate social norms start to gossip might be different from when "ordinary" people do so. "Women who spin by the moon" could be a different standard than "people who talk in the marketplace", for example.