glide, skate, slip, fail in exams, (kokuji)
辷 centers on smooth, uncontrolled motion across a surface: gliding, skating, or slipping. The exam-failure sense extends this as a metaphorical slip or stumble.
辷 is a Japanese kokuji (国字) created by combining the movement radical 辶 with the single stroke 一, likely to represent smooth, linear motion such as gliding or slipping.
The movement radical 辶 wraps around a single flat line 一, like a path that is perfectly smooth. Picture a skate gliding effortlessly along that line.
For すべ, imagine a smooth slide where everything slips: 'smoothly slide' -> すべ. The scene of gliding on ice ties the sound to the kanji's meaning.
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