diff --git a/jaxtyping/_array_types.py b/jaxtyping/_array_types.py
index c31e74a..babdb76 100644
--- a/jaxtyping/_array_types.py
+++ b/jaxtyping/_array_types.py
@@ -86,9 +86,10 @@ class _FixedDim:
 
 
 class _SymbolicDim:
-    def __init__(self, expr, broadcastable):
+    def __init__(self, expr, broadcastable, elem_string):
         self.expr = expr
         self.broadcastable = broadcastable
+        self.elem_string = elem_string
 
 
 _AbstractDimOrVariadicDim = Union[
@@ -122,10 +123,11 @@ def _check_dims(
                 eval_size = eval(cls_dim.expr, single_memo.copy())
             except NameError as e:
                 raise NameError(
-                    f"Cannot process symbolic dimension '{cls_dim.expr}' as some "
-                    "dimension names have not been processed. In practice you should "
-                    "usually only use symbolic dimensions in annotations for return "
-                    "types, referring only to dimensions annotated for arguments."
+                    f"Cannot process symbolic dimension '{cls_dim.elem_string}' as "
+                    "some dimension names have not been processed. In practice you "
+                    "should usually only use symbolic dimensions in annotations for "
+                    "return types, referring only to dimensions annotated for "
+                    "arguments."
                 ) from e
             if eval_size != obj_size:
                 return False
@@ -444,8 +446,9 @@ def _make_array(array_type, dim_str, dtypes, name):
                     "Cannot have symbolic multiple-dimensions, e.g. "
                     "`*foo+bar` is not allowed"
                 )
+            elem_string = elem
             elem = compile(elem, "<string>", "eval")
-            elem = _SymbolicDim(elem, broadcastable)
+            elem = _SymbolicDim(elem, broadcastable, elem_string)
         dims.append(elem)
     dims = tuple(dims)