Family Rynchopidae, also known as the "skimmers," are a group of birds that are characterized by their elongated lower mandibles that are specialized for skimming the surface of the water as they fly. Although the family name is specific, there are a few synonyms that can be used interchangeably to refer to these birds. One of these is the "scissorbills," which refers to their unique beak shape. Another synonym is "sea swallows," which is a reference to their swift and graceful flying patterns. Finally, "cutwater" is a lesser-used term that refers to their ability to slice through the surface tension of the water as they skim for food.