day (a 24-hour period)
day (the period from midnight to the following midnight)
day (the rotational period of a planet, moon or any celestial body (especially Earth))
day, daylight (the period between sunrise and sunset when there is daylight)
day, daylight, light (light from the Sun)
light (open view; a visible state or condition)
day (the part of a day which one spends at work, school, etc.)
day (a specified time or period, considered with reference to the prominence or success (in life or in an argument or conflict) of a person or thing)
convention, congress (a formal assembly)
see Tage for plural-only senses

hello; (good) day