Part of speech: Adjective
willing to undertake or seeking out new and daring enterprises
Example: adventurous pioneers; the risks and gains of an adventuresome economy
The word "adventurous" comes from Old French aventuros, which comes from Middle English aventurous. Many other languages have similar words:
English has both Germanic and French words for the same things—'begin' vs 'commence', 'help' vs 'assist'.