The term 'boil gently' can be summarized by the crossword solution 'SIMMER, ' which is a cooking technique that involves cooking food at a low temperature, just below the boiling point. Simmering is often used to cook delicate foods such as fish or vegetables, as it prevents them from becoming overcooked and tough. Boiling gently is a way of ensuring that food is cooked slowly and evenly, without burning or sticking to the pan.