hang someone out to dry leave someone in a difficult or vulnerable situation. informal

☞ The image here is of hanging wet washing on a clothes line to dry. The idea of 'flapping uselessly or ineffectually' like clothes drying in the wind is also behind the cricketing metaphor hanging your bat out to dry, which dates from the late 19th century and means 'holding your bat away from your body at an ineffectual angle'.

2011Economist The price rises will swiftly be reversed and the bosses responsible … could find themselves hung out to dry.