That dictionary has a narrower definition of risk than what I'm using. You may find the wiki page on risk wiki page on risk more helpful.

In racing it is valid to talk about negative risk (i.e favorable outcome). Maybe it's easier to think of the probability distribution of potential outcomes, where the outcome is measured in time relative to another boat.

Not that I've ever heard of someone imagining a complete probability curve, but you might think someting like "if I go left when the rest of the fleet goes right there's a high chance of slightly unfavorable outcome vs. low chance of highly favorable outcome, the mean result is probably slightly negative".

And then if you're towards the back of the pack and you've got a low throwout you might decide going left is worth it because you don't have much to lose. And if you end up losing by it, you can say "Well, I took a calculated risk that didn't pan out" instead of whining and saying "I was unlucky".