a.

1. 比预期早的，过早的
   This disease produces premature aging of the brain.

   这种疾病使大脑过早衰老。

2. 不成熟的，仓促的，草率的
   She was a bit too premature in giving up this job.

   她放弃这份工作似嫌太草率。

   He ventured a premature opinion at the meeting.

   他在会上大胆发表了一个不成熟的意见。

3. 早产的；早产儿的
   Premature babies are kept alive in incubators.

   早产婴儿放在保育箱里保育。

n.

1. 过早发生的事物
2. 早产儿

adj.

1. occurring or done before the proper time.
2. (of a baby) born before the end of the full term of gestation, especially three or more weeks before.