"Study at deadly" is a popular British English phrase that means to study intensely or to work very hard. The spelling of the word "deadly" in this context is pronounced /ˈdɛdli/ using IPA phonetic transcription. The "e" in "deadly" is pronounced with a short "e" sound, while the "a" is pronounced with a short "a" sound. This phrase is commonly used by students and professionals alike and highlights the importance of dedication and hard work in achieving success.