"I've been workin' on the railroad, all the livelong day." So goes the American folk standard, and nowadays when we encounter the word livelong, it is typically in the phrase "all the livelong day" or something similar. Although we don't see livelong much in prose anymore, poets still love the word, possibly for its two distinct, alliterative syllables. Despite the resemblance, livelong does not mean the same thing as lifelong (as in "a lifelong friend"). In fact, the words are not closely related: the live in livelong derives from lef, a Middle English word meaning "dear or beloved."