136. The "Dancing Legs" Radical: 舛
The Thematic Explorations essay "Sticky Stroke Counts" shows how the 舛 radical gives legs to characters such as 舞 (1761: dance) and analyzes different ways of writing this radical. As long as you're here, though, let's take a quick look at other aspects of this radical.
The Names of 舛
Here's one way to refer to the radical name in both Japanese and English:
舛 (まいあし: the "dancing legs" radical)
This name comes from the 舛 on the bottom of 舞, a kanji with the kun-yomi of まい. The word あし (足) means "legs," which seems fitting here, but in this case the あし alludes to the bottom position of the 舛 radical in 舞. (For more on position names, see "Radical Terms" and click on sections 4 and 5.)
The yomi of 舛 can also be ます. One reason is that the non-Joyo 舛 has a kun-yomi of ます. Also, Kanjigen says that 舛 can serve as an "unofficial variant" (俗字, ぞくじ) of 升, which also has the kun-yomi of ます. That's possible because the calligraphic forms of 升 and 舛 look very much alike.
On Duty in Just One Joyo Kanji
Incidentally, 舞 is the only Joyo kanji to feature 舛 as an on-duty radical. However, three more characters contain this shape as a component:
傑 (1211: outstanding person)
瞬 (1372: instant, moment; to blink, twinkle, wink)
隣 (1915: neighbor)