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.
SIT ON
Meaning of SIT ON in English
American idioms English vocabulary. Английский словарь американских идиом. 2012