fortuitous.

1. Occurring by chance rather than through intention or a planned cause.

2. Happening by chance in a way that brings an advantage or welcome result.

Use it for

Words that belong together

• a fortuitous encounter
• a fortuitous coincidence

On the page

Their fortuitous encounter changed the route she had planned to take.

A fortuitous coincidence brought the two letters to the same desk.

Usage notes

Primary category: literary. Forms: Relational, temporal, or authenticity adjective; ordinary comparative and superlative usually not needed. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings.