To encircle someone or something is to go all the way around it until it is shut in — a ring of people, trees, walls, or soldiers with no real gap. It is stronger than stand around: the idea is a closed circle. You can encircle a child with your arms, a garden with a fence, or a town with troops. The army use is the most serious: if soldiers are encircled, they may have no way out. In everyday talk it is a clear, slightly careful verb; surround is the simpler word most people reach for. People do stretch it to feelings (“worries encircled him”), but the home picture is still a physical ring.