fortuitous

Merriam-Webster's Word of the Day for February 9, 2026 is fortuitous. It is a formal adjective. Fortuitous typically describes something that occurs by lucky chance. It can also mean simply happening by chance. The word also carries the meaning of being fortunate or lucky. An example is a fortuitous coincidence. Arriving at a most opportune moment is also described as fortuitous. Historically, fortuitous solely meant happening by chance, stemming from the Latin word for chance. Over time, its meaning expanded to include "fortunate" or "lucky." This likely happened because it sounds similar to "fortunate" and "felicitous." While some critics dislike this "lucky" sense, it is now widely accepted. However, using it in formal contexts might still be considered risky.