To plug along is to keep working steadily at something, usually without much excitement or speed, and often against difficulty or discouragement. It suggests plodding on rather than sprinting, getting a task done bit by bit through sheer persistence. It is most often used of ordinary, unglamorous effort, such as someone plugging along at their work or a slow project, simply refusing to stop even when progress is limited.
What’s the origin of the phrase ‘plug along’?
The phrase comes from a specific sense of the verb “plug” meaning to work steadily and doggedly at something, to plod or persevere. The Oxford English Dictionary records this sense of “plug” as meaning “to work steadily away at something; to persevere doggedly; to plod, to move steadily,” noting that it is frequently used with “away, along” and similar words attached. The dictionary’s citations for this general sense go back to 1867, though a use matching the modern colloquial “plugging along” specifically is not found until 1900.
Etymonline gives a slightly earlier date for the underlying sense, reporting that the Oxford English Dictionary traces “work energetically at” to around 1865, and cites an illustrative line about being “remembered on the river at Oxford.” That detail hints at a possible origin in university rowing slang, where steady, dogged effort at the oar would have been an everyday idea worth naming. This sense of “plug” is distinct from the later meaning of “plug” as promoting or popularising something through repetition, which Etymonline dates to 1906, so the two uses developed separately.
There may also be a connection between this sense and “plug” as old slang for a worn-out horse, the kind of animal that could only ever move at a steady plod, though it is not clear which sense came first, or whether the two are related at all.
Green’s Dictionary of Slang lists “plug along” alongside “plug at,” “plug away” and “plug on” as fixed variants of this sense of “plug,” all glossed together as meaning to persist or to struggle hard against the odds. The phrase has stayed in everyday use in that plain, workmanlike sense ever since.