Definition
The left side of a vessel as observed by a person aboard facing the bow (front). Larboard is now an obsolete nautical and admiralty term, having been replaced universally by port. The substitution was directed by the English Admiralty on practical grounds: larboard sounded too similar to starboard (the right side) and created dangerous risk of confusion in oral commands aboard ship.
Common Language
Modern common usage (Wiktionary): The left side of a ship, looking from the stern forward to the bow; port side.
Historical common usage (Webster's 1913): The left-hand side of a ship to one on board facing toward the bow; port; opposed to starboard.
The common and legal meanings are effectively identical. The research-relevant point is not a gap between common and legal usage but the term's historical displacement: both general and legal language abandoned larboard in favor of port, and the timing of that transition matters when reading older maritime documents.
Common Confusion
Larboard and port refer to the same side of a vessel and are fully interchangeable in meaning. The confusion that drove larboard out of use was between larboard and starboard — the two antonyms — not between larboard and port. Researchers encountering larboard in early admiralty records should not treat it as a term of art distinct from port; the words are synonyms, and the former simply predates the latter in formal usage.
Why It Matters in Research
Larboard appears with regularity in admiralty pleadings, collision reports, insurance policies, salvage records, and cargo manifests predating the mid-nineteenth century. A researcher working in pre-reform maritime sources — particularly English admiralty materials before the Admiralty's directive and American shipping records of the same era — must recognize larboard as the functional equivalent of port. Failing to do so can produce misreadings of collision narratives or cargo damage descriptions where the position of a vessel or the side of impact is legally determinative.
The transition from larboard to port was not instantaneous across jurisdictions or document types. Informal logs, private correspondence, and American coastal trade documents continued using larboard for some years after the formal English change. The date of a document therefore matters: early nineteenth-century and older sources will use larboard; later sources will use port; a transitional period produces both. Cross-referencing a document's date against this shift is basic navigational hygiene when reconstructing collision sequences or interpreting the spatial language in maritime contracts.
Historical Dictionary Support
Bouvier's is the primary historical legal dictionary source here, and its treatment is both accurate and candid. Bouvier notes that larboard designated the left side when facing the bow, identifies starboard as its opposite, and confirms that larboard was supplanted by port on Admiralty order — citing the acoustic confusion with starboard as the explicit rationale. This is a rare instance of a legal dictionary directly recording the bureaucratic mechanism by which a term was retired.
Webster's 1913 and Wiktionary align precisely with Bouvier on meaning. None of the sources introduces any technical legal content beyond the navigational definition, which is appropriate: larboard carried no specialized legal meaning independent of its nautical one. It was directional vocabulary that courts, insurers, and pleaders borrowed from seamanship, not a term the law reshaped for its own purposes.
What the historical dictionaries collectively omit is any discussion of how the larboard-to-port transition affected document interpretation in litigation — an omission that is practically significant for researchers, though understandable given the dictionaries' general reference function.
Jurisdictional Note
The formal substitution of port for larboard originated with the English Admiralty. American maritime practice followed, but without a single binding directive, so the transition in U.S. documents was somewhat less uniform. Researchers in American admiralty sources from roughly 1840–1870 may encounter both terms within the same jurisdiction or even the same proceeding.