crux

Where does the word "crux" come from? It comes from Latin crux, and was adopted directly into English (1710s).

Crux’s story begins in Latin: crux meant “cross.” A cross, the Roman instrument of execution; also used for torment. It reached English by 1710s as crux. Scholars used 'crux' for a textual puzzle that tormented them; the sense 'central point' followed. Today, crux means the decisive or most important point.

1. Stage 1 · Latin · ancient crux "cross", a cross, the Roman instrument of execution; also used for torment.
2. Stage 2 · English · 1710s crux "crucial point", scholars used 'crux' for a textual puzzle that tormented them; the sense 'central point' followed.