ad infinitum

Where does the word "ad infinitum" come from? It comes from Latin ad infinitum, and was adopted directly into English (1600s).

Ad infinitum’s story begins in Latin: ad infinitum meant “to infinity.” To infinity, from ad (to) and infinitus (unbounded, endless). It reached English by 1600s as ad infinitum. A phrase from scholastic logic, used for chains of reasoning that never end. Today, ad infinitum means continuing endlessly, without limit.

1. Stage 1 · Latin · ancient ad infinitum "to infinity", to infinity, from ad (to) and infinitus (unbounded, endless).
2. Stage 2 · English · 1600s ad infinitum "continuing forever, without end", a phrase from scholastic logic, used for chains of reasoning that never end.