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+*View this file with results and syntax highlighting [here](https://mlochbaum.github.io/BQN/help/under.html).*
+
+# Circle Jot (`⌾`)
+    
+## `𝔽⌾𝔾 𝕩`, `𝕨 𝔽⌾𝔾 𝕩`: Under
+    
+- Apply transformation `𝔾` to all arguments
+- Apply `𝔽` to the transformed arguments
+- Undo transformation `𝔾`
+    
+Where `𝔾` must be 
+    
+1. A function invertible by `⁼` (Undo)
+2. A structural modification
+    
+           9⌾(1⊸⊑) 1‿2‿3
+
+           √⁼ (√1) + (√9)
+
+           1 +⌾√ 9
+
+