sweetheart
/ˈswiːthɑːt/noun
1- used as a term of endearment or affectionate form of address亲爱的（用作爱称）：
don't worry, sweetheart, I've got it all worked out.
别担心, 亲爱的, 我已经把它全解决了。
1.1
- a person that one is in love with恋人, 情人：
the pair were childhood sweethearts.
这一对是青梅竹马的恋人。
1.2
- a particularly lovable or pleasing person or thing特别可爱的人（或物）：
he is an absolute sweetheart.
他是个绝对可爱的人。
1.3
- as modifier informal denoting an arrangement reached privately by two sides, especially an employer and a trade union, in their own interests〈非正式〉私下达成的协议（尤指在工会和雇主之间为各自利益达成的协议）：
a sweetheart agreement.
私下达成的协议。