README: fix typo

README.md

@@ -11,7 +11,7 @@ An ESnext spec-compliant sync iterator helpers shim/polyfill/replacement that wo
 
 This package implements the [es-shim API](https://github.com/es-shims/api) “multi” interface. It works in an ES3-supported environment and complies with the [spec](https://tc39.es/ecma262/#sec-additional-properties-of-the-string.prototype-object).
 
-Because the `Iterator.prototype` methods depend on a receiver (the `this` value), the main export in each subdirectory takes the string to operate on as the first argument.
+Because the `Iterator.prototype` methods depend on a receiver (the `this` value), the main export in each subdirectory takes the iterator to operate on as the first argument.
 
 The main export of the package itself is simply an array of the available directory names. It’s sole intended use is for build tooling and testing.