How to Write 啶 (dìng) — Meaning “-dine (chemical suffix)”

Imagine a fixed chemical structure (定) that you label with a mouth (口) that says 'ding' like a bell. This picture helps you link the sound 'dìng' to its use as a chemical suffix, such as in pyridine and pyrimidine.

Write the left component 口 first with three strokes, making it small and positioned in the upper-left area. Then write 定 (top dot, horizontal, then the rest) with careful balance so the right side does not squeeze the mouth. A common mistake is making 口 too large or misplacing the dot above 定.

啶 has 定 on the right; 呲 has 此 (cǐ, 'this') and means 'to show teeth' or 'to sneer'; 咠 has 耳 (ěr, 'ear') and means 'to whisper'. Visually, 啶 uses a chemical suffix meaning, while 呲 and 咠 are used for actions or sounds, so their contexts are completely different.

啶 is only used as a chemical suffix in scientific terms like 吡啶 (pyridine) and 嘧啶 (pyrimidine). It is not found in everyday conversation or HSK vocabulary. Its 口 radical is a typical way Chinese represents foreign sounds in chemistry, making the character purely technical.

Common words containing 啶 include: 吡啶 (bǐ dìng) — pyridine; 嘧啶 (mì dìng) — pyrimidine; 啶烷 (dìng wán) — dinane (chemical compound).