Refers to the two times of day, often used in contexts like daily routines, temperature differences, or medication schedules.
The morning and evening chill has become severe.
Please take this medicine after meals, morning and evening.
always; all the time; day and night
Adverbial use meaning 'constantly' or 'every day without fail', often implying a habitual or persistent state.
He thinks about work day and night.
The temperature difference between morning and evening is large this time of year.
Please take this medicine in the morning and evening.
Once October comes, it gets cool in the mornings and evenings.