diff --git a/src/compile/modifier.rs b/src/compile/modifier.rs
index 74a3eeff..e8f8df92 100644
--- a/src/compile/modifier.rs
+++ b/src/compile/modifier.rs
@@ -624,14 +624,15 @@ impl Compiler {
                     self.push_instr(Instr::PushFunc(func));
                 }
             }
-            Rear => {
+            Backward => {
                 let operand = modified.code_operands().next().unwrap().clone();
                 let (mut instrs, sig) = self.compile_operand_word(operand)?;
                 if sig.args != 2 {
                     self.add_error(
                         modified.modifier.span.clone(),
                         format!(
-                            "{}'s function must be dyadic, but its signature is {}",
+                            "Currently, {}'s function must be dyadic, \
+                            but its signature is {}",
                             prim, sig
                         ),
                     );
diff --git a/src/primitive/defs.rs b/src/primitive/defs.rs
index 481b5ab2..88343360 100644
--- a/src/primitive/defs.rs
+++ b/src/primitive/defs.rs
@@ -1793,7 +1793,7 @@ primitive!(
     /// It is experimental because it is unclear whether this is a desirable direction for the language.
     /// ex: # Experimental!
     ///   : ¨⊂ 1 2
-    ([1], Flop, Stack, ("flop", '¨')),
+    ([1], Backward, Stack, ("backward", '¨')),
     /// Call a function on two sets of values
     ///
     /// For monadic functions, [both] calls its function on each of the top 2 values on the stack.
diff --git a/src/primitive/mod.rs b/src/primitive/mod.rs
index 10fc80d7..bef6dc17 100644
--- a/src/primitive/mod.rs
+++ b/src/primitive/mod.rs
@@ -395,7 +395,7 @@ impl Primitive {
         use SysOp::*;
         matches!(
             self,
-            (But | Rear)
+            (But | Backward)
                 | (Orient | Coordinate | Astar | Fft | Triangle | Case)
                 | Sys(Ffi | MemCopy | MemFree | TlsListen)
                 | (Stringify | Quote | Sig)
@@ -851,7 +851,7 @@ impl Primitive {
             | Primitive::By
             | Primitive::Gap
             | Primitive::But
-            | Primitive::Rear
+            | Primitive::Backward
             | Primitive::Un
             | Primitive::Under
             | Primitive::Content