Burn the midnight oil' is an idiom that means to stay up late into the night, usually to work or STUDY. The crossword solutions for this term are STUDY (5 letters), CRAM (4 letters), LUCUBRATE (9 letters), PORE (4 letters), STAYUP (6 letters), and WORKLATE (8 letters). To 'STUDY' means to read and learn about a subject in order to gain knowledge. To 'CRAM' is to quickly learn a large amount of information in a short period of time. To 'lucubrate' is to work diligently and intensively on something. To 'PORE' over something is to read or STUDY it carefully. To 'stayup' is to remain awake late into the night. To 'worklate' is to continue working after normal working hours.