The adventitiousness of the island's flora reflected the number of species that arrived by chance.

The rare wildflower appeared adventitiously in the cracks of the old stone wall, surprising every botanist who examined the site.

The adventitious seeds that appeared in the garden likely arrived on a passing bird.

The cardiologist noted adventitial thickening around the artery, which suggested chronic inflammation.

The botanist observed that the seeds were attached adventitially to the stem, rather than originating from the plant itself.