promise of reimbursement in the case of loss; paid to people or companies so concerned about hazards that they have made prepayments to an insurance company
a method of surveying; the area is divided into triangles and the length of one side and its angles with the other two are measured, then the lengths of the other sides can be calculated
a trigonometric method of determining the position of a fixed point from the angles to it from two fixed points a known distance apart; useful in navigation