An ancient instrument used to measure time by the position of a shadow cast by the sun; it typically consists of a graduated plate and a gnomon.

To work or study diligently day and night without stopping. Literally means to burn oil for light to continue when the sun sets.

An instrument that uses the position of the sun's shadow to measure time.

a very brief period of time; literally the time it takes for a shadow on a sundial to move an inch

extremely fast, as if the sun has not even had time to move its shadow; used to describe something happening very quickly or on the spur of the moment

(idiom) to be extremely busy throughout the day with no time for rest

(literary) a moment; a period of time

(literary) the shadow of the sun moves, meaning that a period of time has passed; often used to describe being absorbed in a task for a long time

(literary) describes the extreme pressure and racing against time during the imperial examinations; to value every minute under difficult conditions