also: じょうしん
upper lip
Standard anatomical term for the upper lip in everyday and medical contexts.
She has a habit of biting her upper lip when she's nervous.
I fell and cut my upper lip.
labrum
Only with reading じょうしん
Zoological term for the upper lip-like structure in arthropods and other invertebrates. Read as じょうしん in this specialized sense.
The labrum of insects forms part of the mouthparts.
He bit his upper lip out of nervousness.
I fell and my upper lip swelled up.
Mixed kana-kanji spelling sometimes used for clarity or in children's materials.