阈 (yù): threshold

Meanings

刺激达到阈值时，人就能感觉到。

Yù

When a stimulus reaches the threshold, the person can feel it.

阈的本义是门槛。

Yù

The original meaning of this character is the doorsill.

usage

阈 literally meant a doorsill, the raised threshold of a gate. Modern science borrows it for 阈值, the threshold at which a stimulus or effect begins.

radical

门 mén

door; gate

The gate radical 门 frames the meaning: a threshold is the raised sill at the bottom of a doorway, the line you step over.

phonetic

或 huò

or; perhaps

或 supplies the sound, drifted from huò to yù. It is the phonetic element inside the gate, contributing the reading rather than meaning.

阈 yù