What is Hold up ?
Hold up is (verb) 1. to lift or support something or someone He held up his hand. He held the little boy up so that he could see the procession. The roof is held up by those pillars. 2. to make someone or something late The planes were held up by fog. Government red tape is holding up the deal. 3. to attack and rob someone Six gunmen held up the security van.
source: Easier English, Student Dictionary Upper Intermediate Level