What does いびき (ibiki) mean?

Example sentences

• 父(ちち)のいびきがうるさくて眠(ねむ)れなかった。

  My father's snoring was so loud I couldn't sleep.

• 疲(つか)れている時(とき)ほどいびきをかきやすい。

  The more tired you are, the more likely you are to snore.