say it: fawr-TOO-i-tuhs
fortuitous is an adjective meaning "having no cause or apparent cause". It carries 2 recorded senses.
having no cause or apparent cause
“a causeless miracle”
“fortuitous encounters--strange accidents of fortune”
“we cannot regard artistic invention as...uncaused and unrelated to the times”
occurring by happy chance
“profits were enhanced by a fortuitous drop in the cost of raw materials”
Definitions, synonyms and semantic relations for fortuitous come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.