Main Difference
The main difference between Afternoon and Evening is that the Afternoon is a time of the day between noon and evening and Evening is a period of the day from 6:00 PM until nighttime
Afternoon
Afternoon is the time of day from noon or lunchtime until evening. There is no exact definition of the time when afternoon ends and evening starts. (This is equally true for “evening” and “night”.) However afternoon is often taken to start directly after noon (12:00pm). Afternoon ends and evening starts at roughly 5pm or 6pm or maybe just before sunset. Afternoon is the time when the Sun is descending from its zenith in the sky to somewhat before its terminus in the westerly horizon. In human life, it occupies roughly the latter half of the standard working and school day. In literal terms, it refers to a time specifically after noon.
Evening
Evening is the period of time from the end of the afternoon to the beginning of night. Exact time when evening begins and ends (as with night) depends on location and varies throughout the year. Its earliest part of a short period is evening twilight.
The word ‘evening’ may be casually used to include the last waning afternoon shortly before sunset. There can be no precise definition in terms of clock time, but it is casually considered to start as early as 5 p.m. by some, or at 6 p.m. by the OED, and to last until night or bedtime.
Afternoon (noun)
The part of the day from noon or lunchtime until sunset, evening, or suppertime or 6pm.
Afternoon (noun)
The later part of anything, often with implications of decline.
Afternoon (noun)
A party or social event held in the afternoon.
Afternoon (adverb)
In the afternoon.
Afternoon (interjection)
clipping of good afternoon.
Evening (noun)
The time of the day between dusk and night, when it gets dark.
Evening (noun)
The time of the day between the approximate time of midwinter dusk and midnight (compare afternoon); the period after the end of regular office working hours.
Evening (noun)
A concluding time period; a point in time near the end of something; the beginning of the end of something.
“It was the evening of the Roman Empire.”
Evening (noun)
A party or gathering held in the evening.
Afternoon (noun)
the time from noon or lunchtime to evening
“I’ll be back at three in the afternoon”
“I telephoned this afternoon”
“she worked on Tuesday afternoons”
Afternoon (adverb)
in the afternoon; every afternoon.
Afternoon (interjection)
short for good afternoon