Merriam-Webster Collegiate Dictionary - purslane

 noun  Etymology: Middle English, from Anglo-French porsulaigne, from Late Latin porcillagin-, porcillago, alteration of Latin porcillaca, alteration of portulaca  Date: 14th century any of a family (Portulacaceae, the ~ family) of cosmopolitan usually succulent herbs; especially a fleshy-leaved trailing plant (Portulaca oleracea) with tiny yellow flowers that is a common troublesome weed but is sometimes eaten as a potherb or in salads