The term 'round up' is used to describe the process of gathering animals or people together. The crossword solutions for this term are CORRAL (6 letters), HERD (4 letters), PENI (4 letters), AMASS (5 letters), and CLUSTER (7 letters). CORRAL refers to an enclosure used to contain animals, usually made of wood or stone. HERD is a group of animals that travel together, usually led by a dominant animal. PENI is a small enclosure used to contain animals, usually made of wire or metal. AMASS is to collect or gather a large number of things together. CLUSTER is a group of similar things that are close together.