A pickled cucumber , most often simply called a pickle in the United States and Canada , is a cucumber that has been processed in a brine , vinegar , or other solutions and left to ferment for a period of time . A pickled cucumber ( commonly known as a pickle in Australia , Canada , and the United States or generically as Gherkins in the UK ) is a cucumber that has been pickled in a brine , vinegar , or other solution and left to ferment for a period of time , by either immersing the cucumbers in an acidic solution or through souring by lacto-fermentation .