Fortuitous
FORTU'ITOUS, adjective [Latin fortuitus, from the root of fors, forte, fortuna. The primary sense is to come, to fall, to happen. See Fare.]
Accidental; casual; happening by chance; coming or occurring unexpectedly, or without any known cause. We speak of fortuitous events, when they occur without our foreseeing or expecting them, and of a fortuitous concourse of atoms, when we suppose the concourse not to result from the design and power of a controlling agent. But an event cannot be in fact fortuitous [See Accidental and Casual.]