You can not delete the app from google play store but you can unpublished it. After unpublishing you can again republish it later on when required.
Following are the steps to unpublished app on the Google play store:
- Login into https://market.android.com/publish/Home.
- Select the application you want to delete from google play store.
- Click on the “Store Presence” menu in the left corner, and then click the “Pricing and Distribution” item.
- Click Unpublish.
- Submit Update.