to serve as; to work as; to be in charge of; at that time; just then; to face; should; ought to
当 works two ways: dāng for being or facing something (当时 'at that time'), and dàng for treating something as, or being fooled (上当).
GF0025–2021 character list · 二级, 六级WHOLE GLYPH & STRUCTURE
ZDIC treats the old form 當 as 形声: 尚 as sound over 田 as meaning. The modern simplified 当 writes a small-dot crown over 彐 — the top is the visual remnant of the old sound side, and the bottom piece no longer shows 田.
WHOLE CHARACTER
to serve as; to work as; to be in charge of; at that time; just then; to face; should; ought to
当 works two ways: dāng for being or facing something (当时 'at that time'), and dàng for treating something as, or being fooled (上当).
ZDIC treats the old form 當 as 形声: 尚 as sound over 田 as meaning. The modern simplified 当 writes a small-dot crown over 彐 — the top is the visual remnant of the old sound side, and the bottom piece no longer shows 田.
TOP: SMALL-DOT CROWN (VISUAL REMNANT OF THE OLD SOUND SIDE 尚)
a small crown of dots and a vertical (bound form)
A bound top piece used at the top of several characters; each page shows its role in that character.
In 当: top: small-dot crown (visual remnant of the old sound side 尚) Shown with its documented or clearly limited role.
BOTTOM WRITTEN PIECE (THE OLD FORM HAD 田 HERE)
a bound graph (dictionary radical)
A bound written piece used inside several characters; not a standalone modern word.
In 当: bottom written piece (the old form had 田 here) Shown with its documented or clearly limited role.
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