monger

Yuval Noah Harariの "Sapiens" を読んでいます。 'The Tree of Knowledge' の章から引用します。

Do you think that history professors chat about the reasons for World War One when they meet for lunch, or that nuclear physicists spend their coffee breaks at scientific conferences talking about quarks? Sometimes. But more often, they gossip about the professor who caught her husband cheating, or the quarrel between the head of the department and the dean, or the rumours that a colleague used his research funds to buy a Lexus. Gossip usually focused on wrongdoings. Rumour-mongers are the original fourth estate, journalists who inform society about and thus protect it from cheats and freeloaders.

"Rumour-mongers" は "fishmonger" からと、その後に "the original fourth estate, journalists" とあるので凡その意味は分かりますが、"monger" の用法をを辞書で確認します。

・Collins Dictionary: 1. (in combination except in archaic use) a trader or dealer: ironmonger 2. (in combination) a promoter of something unpleasant: warmonger
・Cambridge English Dictionary: a person who encourages a particular activity, especially one that causes trouble: They're nothing but a bunch of war-mongers.
・Vocabulary.com: A monger is a seller, especially of something specific like a fish monger or an iron monger.
You can use the noun monger as a word on its own, although it frequently shows up as a suffix, in words like cheesemonger. Monger can also be used as a verb meaning "to sell or peddle." In both cases, the word is a bit old fashioned, used more often these days to describe a person who promotes something hurtful, as in warmonger. The Old English root word is mangere, "merchant or broker," from the Latin mango, "dealer or trader."