Two meanings, both tracing back to the Seven Sages of the Bamboo Grove: (1) the small, soprano member of the ruan lute family; (2) a literary term for 'nephew', because the poet Ruan Xian
阮咸 was the nephew of the senior sage Ruan Ji
阮籍 — the pair became known as
大阮 (elder) and
小阮 (junior). 《
新华词典》 records both senses.