Sailing and steaming are both still-common maritime terms, but neither refers literally to their historical origin on a modern merchant ship.
Sailing: A General Term for Departure/Voyage
“The ship sails at 0600” or “we sail for Singapore tomorrow” uses “sailing” in its general sense — meaning departure or the voyage itself — a linguistic holdover from the age of actual sailing ships, now used regardless of whether the vessel has sails at all. No modern merchant ship “sails” in the literal sense; the word has simply persisted as general maritime vocabulary for departure and voyage.
Steaming: A Holdover From the Steam Engine Era
“Steaming at 14 knots” or “steaming time to port” uses “steaming” to describe a vessel underway under engine power — again, a term surviving from when ships were literally propelled by steam engines. Modern merchant ships are diesel-powered (or increasingly, alternative fuels), not steam-powered, but “steaming” remains standard vocabulary for “underway under power.”
Why Both Terms Persisted
Maritime vocabulary is famously conservative — many terms survive long after the technology that originated them has been replaced, because they remain functionally useful shorthand understood by everyone in the industry. “Steaming time,” “full ahead,” and similar terms work the same way — practical, universally understood terminology, regardless of literal technical accuracy.
Practical Usage Today
- “Sailing” / “sailing time” — used for departure and voyage generally
- “Steaming” / “steaming time” / “steaming distance” — used specifically for time/distance underway under engine power, particularly in voyage planning and reporting contexts
Neither term should be taken literally on a modern engine-powered merchant vessel — both are simply retained maritime shorthand.
Exam Relevance
Correct, contextual use of “sailing” and “steaming” terminology is covered within general Ship Knowledge and Navigation vocabulary in deck officer competency exams.