The Irishman, 19, has been on loan at the Glovers during the latter part of the season.
And now their manager, Russell Slade, has decided to acquire the services of the striker on a two-year deal.
Slade said: "I am really pleased to have secured Aidan's services for the next two years. He made a good start with us and topped that off with a great goal against Swansea.
"I hope that's the first of many for Yeovil."