faint, far off
緲 centers on something visually indistinct or distant: appearing faint, blurred, or far off in space.
緲 combines 糸 (thread) with 眇, which likely contributes both sound and the idea of something tiny or indistinct, suggesting a thread so fine it is barely visible.
The thread radical 糸 beside 眇 (which looks like an eye 目 with a tiny stroke) suggests a thread so fine that it is faint and hard to see, like something far off.
For ビョウ, imagine a faint, far-off thread that looks like a tiny 'byō' (びょう) — a tack or pin — barely visible in the distance: byō -> ビョウ.
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