year (岁首, 岁月); age; years old (周岁); harvest (歉岁)
岁 is a year of age — 岁数 counts them, 岁月 names the years gone by.
GF0025–2021 character list · 一级WHOLE GLYPH & STRUCTURE
ZDIC says the formation was originally 形声 for the older 歲; the modern 山-over-夕 form is shown as pieces without a phonetic rule.
WHOLE CHARACTER
year (岁首, 岁月); age; years old (周岁); harvest (歉岁)
岁 is a year of age — 岁数 counts them, 岁月 names the years gone by.
ZDIC says the formation was originally 形声 for the older 歲; the modern 山-over-夕 form is shown as pieces without a phonetic rule.
TOP PIECE (THE RADICAL 山)
mountain; hill
Standalone meaning is kept separate from its role in other characters.
In 岁: top piece (the radical 山) ZDIC lists 山 as the radical.
LOWER PIECE (夕)
evening
Standalone meaning is kept separate from its role in other characters.
In 岁: lower piece (夕) Shown as the lower piece; 夕's standalone meaning is not claimed here.
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