diff --git a/src/Terminal.ts b/src/Terminal.ts
index 989bc16c..f0c6100e 100644
--- a/src/Terminal.ts
+++ b/src/Terminal.ts
@@ -584,7 +584,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
     }, true));
 
     this.register(addDisposableDomListener(this.element, 'keyup', (ev: KeyboardEvent) => {
-      if (!wasMondifierKeyOnlyEvent(ev)) {
+      if (!wasModifierKeyOnlyEvent(ev)) {
         this.focus();
       }
 
@@ -1954,7 +1954,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
  * Helpers
  */
 
-function wasMondifierKeyOnlyEvent(ev: KeyboardEvent): boolean {
+function wasModifierKeyOnlyEvent(ev: KeyboardEvent): boolean {
   return ev.keyCode === 16 || // Shift
     ev.keyCode === 17 || // Ctrl
     ev.keyCode === 18; // Alt