A lake, a body of water that is surrounded by land, can be described by different words or synonyms. Some of these synonyms include pond, lagoon, reservoir, tarn, and mere. A pond is a small lake, while a lagoon is a shallow body of water separated from the ocean by a strip of land. A reservoir is a man-made lake used to store water. A tarn is a small mountain lake formed in a cirque or basin. Lastly, a mere is a shallow, isolated lake that is often seasonal in nature. All of these synonyms provide different characteristics and contexts for describing bodies of water that we commonly refer to as "lakes".