横插一杠子

横插一杠子

Literally means:

an intruding big stick in between

Actually means:

deliberate intervention or hindrance

杠子 is thick stick. In a figurative sense, the phrase refers to setting up obstacles so as to stop somebody from doing something smoothly. With its implication of deliberate obstruction and sabotage,such acts always make other feel repugnant or even sick. Derogatory.

杠子指粗棍子。比喻设置障碍使别人的事情不能顺利进行。含有故意阻挠或破坏，因而令人反感甚至厌恶的意味。具有贬义色彩。