Английский словарь американских идиом - sit on

{v.} 1. To be a member of (a jury, board, commission), etc. * /Mr. Brown sat on the jury at the trial./ 2. {informal} To prevent from starting or doing something; squelch. * /The teacher sat on Fred before he could get started with the long story./ * /The teacher sat on Joe as soon as he began showing off./