When you do something praiseworthy, you should be congratulated and admired for doing it. Diving into the ocean to save a drowning child is praiseworthy.
Use the adjective praiseworthy to describe an action that deserves acclaim or celebration. It's praiseworthy to treat everyone with kindness, and it's also praiseworthy to discover a cure for cancer or learn to speak ten languages. The fifteenth century word comes from a shortening of "worthy of praise," and it was originally hyphenated: praise-worthy. Praise has an Old French root, pretium, "to prize or to praise."