throw the baby out with the bathwater

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throw out the baby with the bath water

Alternative forms

throw out the baby with the bathwater, throw out the baby with the bath water, throw the baby out with the bath water

Etymology

From a calque of German schüttet das Kind mit dem Bade aus, a proverb that dates to 1512. First recorded by Thomas Murner in his satire Narrenbeschwörung. First appeared in English when Thomas Carlyle translated it and used it in an 1849 essay on slavery.

Pronunciation

(Received Pronunciation) IPA^(key): /θɹəʊ ðə ˈbeɪbi aʊt wɪð ðə ˈbɑːθwɔːtə(ɹ)/
(General American) IPA^(key): /θɹoʊ ðə ˈbeɪbi aʊt wɪθ ðə ˈbæθwɔtɚ/
Audio (General Australian): (file)

Verb

throw the baby out with the bathwater (third-person singular simple present throws the baby out with the bathwater, present participle throwing the baby out with the bathwater, simple past threw the baby out with the bathwater, past participle thrown the baby out with the bathwater)

(idiomatic) To discard, inadvertently or through overzealousness, something valuable or essential ("the baby") in the process of removing or rejecting something unwanted or undesirable ("the bathwater").
They cancelled the entire project because the new management didn't like the prototype, but I think they threw the baby out with the bathwater.

Translations

(idiomatic) to discard the valuable along with the unwanted

Czech: vylít vaničku i s dítětem
Danish: kaste barnet ud med badevandet, smide barnet ud med badevandet
Dutch: het kind met het badwater weggooien (nl)
Finnish: heittää lapsi pois pesuveden mukana, heittää lapsi pesuveden mukana
French: jeter le bébé avec l'eau du bain (fr)
German: das Kind mit dem Bade ausschütten (de)
Hebrew: שפך את התינוק עם המים (he)
Hungarian: a fürdővízzel együtt a gyereket is kiönti (hu)
Icelandic: að kasta barninu út með baðvatninu
Irish: an t-asal a dhíol leis an adhastar
Italian: buttare il bambino con l'acqua sporca
Japanese: 角を矯めて牛を殺す (tsuno o tamete ushi o korosu, literally “straighten the horns and (thereby) kill the cow”)
Norwegian:
Bokmål: helle barnet ut med badevannet, kaste barnet ut med badevannet, slå barnet ut med badevannet

Nynorsk: slå ut barnet med badevatnet
Polish: wylewać dziecko z kąpielą impf, wylać dziecko z kąpielą (pl) pf
Portuguese: deitar fora a criança com a água do banho (Portugal), jogar fora o bebê com a água do banho (Brazil)
Russian: вме́сте с водо́й вы́плеснуть и ребёнка (vméste s vodój výplesnutʹ i rebjónka), вы́плеснуть ребёнка вме́сте с водо́й (výplesnutʹ rebjónka vméste s vodój)
Swedish: kasta ut barnet med badvattnet (sv)

References

“Don't throw the baby out with the bathwater”, in BBC Learning English, BBC, 14 October 2014