diff --git a/flang/include/flang/Optimizer/Dialect/FIROps.td b/flang/include/flang/Optimizer/Dialect/FIROps.td
--- a/flang/include/flang/Optimizer/Dialect/FIROps.td
+++ b/flang/include/flang/Optimizer/Dialect/FIROps.td
@@ -1061,7 +1061,7 @@
         - shape: emboxing an array may require shape information (an array's
           lower bounds and extents may not be known until runtime),
         - slice: an array section can be described with a slice triple,
-        - lenParams: for emboxing a derived type with LEN type parameters,
+        - typeparams: for emboxing a derived type with LEN type parameters,
         - accessMap: unused/experimental.
   }];
 
@@ -1069,7 +1069,7 @@
     AnyReferenceLike:$memref,
     Optional<AnyShapeType>:$shape,
     Optional<fir_SliceType>:$slice,
-    Variadic<AnyIntegerType>:$lenParams,
+    Variadic<AnyIntegerType>:$typeparams,
     OptionalAttr<AffineMapAttr>:$accessMap
   );
 
@@ -1085,7 +1085,7 @@
   ];
 
   let assemblyFormat = [{
-    $memref (`(` $shape^ `)`)? (`[` $slice^ `]`)? (`typeparams` $lenParams^)?
+    $memref (`(` $shape^ `)`)? (`[` $slice^ `]`)? (`typeparams` $typeparams^)?
       (`map` $accessMap^)? attr-dict `:` functional-type(operands, results)
   }];
 
@@ -1094,8 +1094,8 @@
   let extraClassDeclaration = [{
     mlir::Value getShape() { return shape(); }
     mlir::Value getSlice() { return slice(); }
-    bool hasLenParams() { return !lenParams().empty(); }
-    unsigned numLenParams() { return lenParams().size(); }
+    bool hasLenParams() { return !typeparams().empty(); }
+    unsigned numLenParams() { return typeparams().size(); }
   }];
 }
 
diff --git a/flang/lib/Optimizer/CodeGen/PreCGRewrite.cpp b/flang/lib/Optimizer/CodeGen/PreCGRewrite.cpp
--- a/flang/lib/Optimizer/CodeGen/PreCGRewrite.cpp
+++ b/flang/lib/Optimizer/CodeGen/PreCGRewrite.cpp
@@ -99,7 +99,7 @@
     }
     auto xbox = rewriter.create<cg::XEmboxOp>(
         loc, embox.getType(), embox.memref(), shapeOpers, llvm::None,
-        llvm::None, llvm::None, embox.lenParams());
+        llvm::None, llvm::None, embox.typeparams());
     LLVM_DEBUG(llvm::dbgs() << "rewriting " << embox << " to " << xbox << '\n');
     rewriter.replaceOp(embox, xbox.getOperation()->getResults());
     return mlir::success();
@@ -128,7 +128,7 @@
       }
     auto xbox = rewriter.create<cg::XEmboxOp>(
         loc, embox.getType(), embox.memref(), shapeOpers, shiftOpers,
-        sliceOpers, subcompOpers, embox.lenParams());
+        sliceOpers, subcompOpers, embox.typeparams());
     LLVM_DEBUG(llvm::dbgs() << "rewriting " << embox << " to " << xbox << '\n');
     rewriter.replaceOp(embox, xbox.getOperation()->getResults());
     return mlir::success();
diff --git a/flang/lib/Optimizer/Dialect/FIROps.cpp b/flang/lib/Optimizer/Dialect/FIROps.cpp
--- a/flang/lib/Optimizer/Dialect/FIROps.cpp
+++ b/flang/lib/Optimizer/Dialect/FIROps.cpp
@@ -521,7 +521,7 @@
     } else {
       return op.emitOpError("LEN parameters require CHARACTER or derived type");
     }
-    for (auto lp : op.lenParams())
+    for (auto lp : op.typeparams())
       if (!fir::isa_integer(lp.getType()))
         return op.emitOpError("LEN parameters must be integral type");
   }