Is there a terminology for "the worst winning move"? What do people call a move which maintains a winning position but is the worst among all such moves?
For example, h8=N+ is such a move in the following game:
[FEN &quot;8/7P/6k1/8/8/8/B1K5/8 w - - 0 1&quot;]

1. h8=N+

I will not normally play such moves in serious games, but in casual games such moves might be good practice for endgame skills.
The short answer is no.
In 25 years of chess experience I have never heard such a term. There isn't unless there is some definition somewhere in a shady club packed with sadists who love to mate with several knights!