掩：遮蔽,遮盖；盗：偷.偷铃铛怕别人听见而捂住自己的耳朵.比喻自己欺骗自己,明明掩盖不住的事情偏要想法子掩盖.
出处：《吕氏春秋·自知》：“百姓有得钟者,欲负而走,则钟大不可负.以椎毁之,钟况然有声.恐人闻之而夺己也,遽掩其耳.”
掩耳盗铃
yan er dao ling
1.to plug one's ears while stealing a bell; to deceive oneself; to bury one's head in the sand; to play the ostrich