Hope Smith wrote:I am looking for open source built-in dictionary to use it in my code
Hi Hope, and welcome to JavaRanch.
My suggestion would be to SearchFirst (←click). A quick Google of "Java open source english dictionary" got me a pile of hits. If you then have a question about a specific OS dictionary, you're much more likely to get a good response.
Isn't it funny how there's always time and money enough to do it WRONG?