How to Write 碘 (diǎn) — Meaning “Iodine”

Imagine a stone (石) that looks like a classic book (典) — but instead of reading it, you find it is actually a bottle of iodine tincture. The "book" shape of 典 helps you recall the sound "diǎn", and the stone radical reminds you it's a solid element.

Write the left radical 石 first (horizontal, left-down stroke, then right-down stroke), then the right part 典. A common mistake is making the 典 portion too wide or misplacing the two horizontal lines inside — keep them evenly spaced and slightly shorter than the top and bottom. The overall width should be balanced, with the right side slightly narrower than the left.

The character 砦 (zhài) means "stockade" and has 此 (this) below the stone radical, not 典. 硅 (guī) means "silicon" and has 圭 (a pile of earth) on the right instead of 典. In contrast, 碘 always contains the phonetic component 典 and is only used for iodine or iodine-related terms.

You most often see 碘 in scientific, medical, or dietary contexts, such as 碘酒 (iodine solution) for disinfecting wounds, and 碘盐 (iodized salt) to prevent iodine deficiency. In China, adding 碘 to table salt is a common public health practice, so the character appears on food packaging and in health articles.

Common words containing 碘 include: 碘酒 (diǎn jiǔ) — Iodine solution; 碘盐 (diǎn yán) — Iodized salt; 补碘 (bǔ diǎn) — Iodine supplement.