killing two birds with one stone; achieving two things at once
A four-character idiom meaning to accomplish two objectives with a single action. Similar in meaning to 一石二鳥, but less common in everyday speech.
This plan aims to kill two birds with one stone.
Let's think of a plan that serves two ends at once.
一石二鳥 is the more common and colloquial equivalent of 一挙両全, both meaning 'killing two birds with one stone'. 一挙両全 is more formal and less frequently used.
A yojijukugo (four-character idiom) composed of 一挙 (one action) and 両全 (both fulfilled). The exact historical origin is uncertain, but it follows a common pattern of classical Chinese-derived idioms.