- [countable]
a small hard shiny white ball that forms inside the shell of an oyster and is of great value as a jewel 珍珠 
a string of pearls 一挂珍珠 a pearl necklace 珍珠项链 She was wearing her pearls (= a necklace of pearls). 她戴着她的珍珠项链。
- [countable]
a copy of a pearl that is made artificially 人造珍珠 - (also mother-of-pearl)[uncountable]
the hard smooth shiny substance in various colours that forms a layer inside the shells of some types of shellfish and is used in making buttons and for decoration 珍珠 pearl buttons 珍珠母纽扣
- [countable, usually singular]
a thing that looks like a pearl in shape or colour （形状或颜色）像珍珠之物 pearls of dew on the grass 草上的露珠
- [countable]
a thing that is very highly valued 极有价值的东西
Word Originlate Middle English: from Old French perle, perhaps based on Latin perna ‘leg’, extended to denote a leg-of-mutton-shaped bivalve.
Idioms
cast, throw, etc. pearls before swine
to give or offer valuable things to people who do not understand their value 明珠暗投；对牛弹琴
a pearl of wisdom
- (usually ironic)
a wise remark 睿智的语言；隽语；妙语 Extra Examplesstudents eager to catch pearls of wisdom from the professor's lips 渴望从教授口中得到至理名言的学生 They would treat these pearls of wisdom with some scepticism. 他们会对这些智慧之珠持怀疑态度。 His journals are full of dubious pearls of homespun wisdom. 他的日记中记下了许多朴素却不可靠的箴言。