Here is a sample frontend form which is using the Owlbot dictionary API. You can search for a different word to try it and switch between the web view and JSON response.
The source code of this sample usage which is a Vue.js component is available at [email protected]:payamnj/owlbot-sample-vue.js.git.
For javascript we have a simple npm package.
As you have noticed from the cURL request, to use the Owlbot API, you need an API token for authhntication.