Is there a textbook distinction between tenebrism and chiaroscuro?

I’m knee-deep in an art history paper, and, from what I’ve been reading, it seems like chiaroscuro and tenebrism are essentially the same thing.

Dictionary definitions:

chiaroscuro:
1. The technique of using light and shade in pictorial representation.
2. The arrangement of light and dark elements in a pictorial work of art.

tenebrism:
a style of painting especially associated with the Italian painter Caravaggio and his followers in which most of the figures are engulfed in shadow but some are dramatically illuminated by a beam of light usually from an identifiable source

If they are technically distinct, what are the telling cues that a painting uses one as opposed to the other? Is there a fine line between them?