Japanese

Noun

膝の皿 ‎(hiragana ひざのさら, romaji hiza no sara)

1. (anatomy) the kneecap, the patella

Usage notes

Both 膝の皿 ‎(hiza no sara) and 膝皿 ‎(hiza sara) are in use in modern Japanese, with 膝の皿 ‎(hiza no sara) used more frequently. The term 膝蓋骨 ‎(shitsugaikotsu) is somewhat more technical, a bit like English patella compared to kneecap.

Synonyms

• 膝蓋骨 (しつがいこつ) ‎(shitsugaikotsu)
• 膝皿 (ひざさら) ‎(hiza sara)
• 膝頭 (ひざがしら) ‎(hizagashira)

Idioms

• 膝 (ひざ)の皿 (さら)から火 (ひ)が出 (で)る ‎(hiza no sara kara hi ga deru): "fire comes out of one's kneecaps" → To be extremely down and out.
• 膝 (ひざ)の皿 (さら)に火 (ひ)が付 (つ)く ‎(hiza no sara ni hi ga tsuku): "one's kneecaps catch on fire" → To be extremely down and out.

References

1. 1 2 2006, 大辞林 (Daijirin), Third Edition (in Japanese), Tōkyō: Sanseidō, ISBN 4-385-13905-9