"The descent is deep."
Translation:El descenso es profundo.
Hmm, just looked at the Words list you mentioned. "Profundo" is listed as last practiced 1 month ago but "hondo" isn't listed at all. List, sorted alphabetically, goes from "hombros" straight to "hongos". Since I've completed the tree twice and refreshed it completely a few times, I would think I would have been shown the word before now. Oh, well. Live and learn...
Thanks for the pointer to the Words list.
A steep descent in physics, rappelling/spelunking, parachuting or flying refers to angle, not rate or depth (aka 'deep'). It's been 20 years since my scuba cert so I'm not sure about current lingo there. So, I guess it depends on what sport this thread is referring to - I can think of dozens of candidates, but I'm guessing the author was referring to something more common - water related. :-)