Petroleum dictionary is an offline dictionary. It contains almost every popular words in petroleum engineering. It is suitable not only for student of petroleum engineering department, but also for those who are working in oil field. Some terms are also related to geology and geophysics which make this apps is also suitable for geologists and geophysicists. On first installation, you will see a box showing the loading progress on the screen, let the loading progress finished otherwise the database is not fully loaded. You might need a few seconds until the database is fully loaded. If you accidentally close the apps when the loading progress if not finished, go to: Setting – Apps – Petroleum Dictionary – Clear data Reopen the petroleum dictionary and wait until the loading progress reach 100%. Features: 1. Offline dictionary 2. Super fast search 3. Word suggestions 4. Small size apps