The term 'made watertight' can be achieved by using three different methods: caulking, calking, and sealing. Caulking is a process of filling gaps or cracks with a material such as putty, cement, or plastic to prevent water from entering. Calking is a process of using a material such as tar, pitch, or wax to fill the seams between two surfaces to make them watertight. Sealing is a process of using a material such as rubber, plastic, or metal to cover a surface to make it watertight. All three processes are used to make surfaces watertight and prevent water from entering.