“Battled-hardened,” Is this one of New Yorker's renowned idiosyncrasies?

Solution 1:

There are lots of cases where the first piece is an adjective (even a participle) or an adverb instead of a noun, but battle-hardened is not one of those. Therefore it really must be a typo, because it means hardened by battle.

Most of the compounds where the second piece is a past participle and the first piece a noun work that way. For example:

air-cooled, belt-driven, carbon-dated, deer-proofed, feather-topped, hand-sewn, gas-powered, iron-plated, jet-propelled, knife-edged, love-begotten, market-tested, need-rooted, oil-tempered, punch-drunk, quarter-sawed, rain-proofed, store-boughten, tailor-made, user-oriented, vacuum-packed, wind-swept, X-linked, yeast-bitten, and zero-padded.

Those all mean “verbed by/with/for (the/a) noun”.

There are also many versions where the first part is a noun but the second part is now a present participle instead of a past participle. These mean “verbing (the/a) noun”. For example:

air-breathing, body-snatching, class-leading, death-defying, deep-searching, earth-moving, fact-finding, gas-guzzling, hair-splitting, iron-binding, jaw-breaking, key-winding, king-killing, labour-saving, market-leading, night-flowering, orange-fuming, penny-pinching, rabble-rousing, sabre-rattling, thought-provoking, underside-couching, water-bearing, and yuck-making.

However, there are some that admit both versions, like fork-tailed and forked-tailed, so it is not a bad question that you have asked.

There do exist other examples where both halves are in participle form besides just forked-tailed, but these occur at about three orders of magnitude less frequency than the first set. Other examples like that are words such as broken-hearted and cloven-hoofed.

Those work more like big-hearted, deep-rooted, half-baked, etc., because the first word is no longer a noun but a modifier, either an adjective or an adverb.

Addendum

Appending the text of Janus’s insightful comment so that its text not be lost, and be searchable:

Words like broken-hearted also have in common that the second member of the compound is a noun, rather than a verb, to which has simply been added an adjectival suffix -ed. They’re not real past participles. You can (just about) consider to battle-harden or to wind-sweep a verb, but there is no such verb as to forked-tail or to broken-heart.

Solution 2:

"Battled-hardened" is not correct, as others have pointed out.

Sometimes, people make spelling mistakes because they're thinking of two words at once, and what they write is a mixture of the two. Maybe the author of this piece was confused because she or he was thinking of the word embattled, whose meanings include

Subject to or troubled by battles, controversy or debates.