diff --git a/typings/xterm-headless.d.ts b/typings/xterm-headless.d.ts
index d39a7098..04732cea 100644
--- a/typings/xterm-headless.d.ts
+++ b/typings/xterm-headless.d.ts
@@ -48,11 +48,6 @@ declare module 'xterm-headless' {
      */
     convertEol?: boolean;
 
-    /**
-     * The number of columns in the terminal.
-     */
-    cols?: number;
-
     /**
      * Whether the cursor blinks.
      */
@@ -145,11 +140,6 @@ declare module 'xterm-headless' {
      */
     rightClickSelectsWord?: boolean;
 
-    /**
-     * The number of rows in the terminal.
-     */
-    rows?: number;
-
     /**
      * Whether screen reader support is enabled. When on this will expose
      * supporting elements in the DOM to support NVDA on Windows and VoiceOver
@@ -210,6 +200,22 @@ declare module 'xterm-headless' {
     windowOptions?: IWindowOptions;
   }
 
+  /**
+   * An object containing additional options for the terminal that can only be
+   * set on start up.
+   */
+  export interface ITerminalInitOnlyOptions {
+    /**
+     * The number of columns in the terminal.
+     */
+    cols?: number;
+
+    /**
+     * The number of rows in the terminal.
+     */
+    rows?: number;
+  }
+
   /**
    * Contains colors to theme the terminal with.
    */
@@ -558,7 +564,7 @@ declare module 'xterm-headless' {
      *
      * @param options An object containing a set of options.
      */
-    constructor(options?: ITerminalOptions);
+    constructor(options?: ITerminalOptions & ITerminalInitOnlyOptions);
 
     /**
      * Adds an event listener for when the bell is triggered.