What does altitude mean?
Altitude denotes the vertical distance of an object or point above a chosen reference level, most commonly sea level or the ground beneath it. It is indispensable in aviation, where pilots speak of cruising at a given altitude; in geography and mountaineering, where it distinguishes high-altitude terrain; and in medicine, where reduced air pressure at great heights produces the well-known condition of altitude sickness. The word also carries a figurative sense, describing an exalted social or professional position, echoing its Latin root altus, meaning 'high'. Measured in feet or metres depending on national convention, altitude differs from elevation, which usually refers to the height of land itself rather than of objects moving above it. Its rhyming kinship with words like latitude and attitude reflects their shared classical ancestry. Precise, technical, yet capable of poetic use, altitude is a term that connects everyday language with some of humanity's oldest ambitions: to rise above the ordinary world.
nounThe height of an object or point in relation to sea level or ground level. Also used figuratively to mean a high position or elevated rank.
- The vertical height of an object or point above a given reference level, especially sea level or ground level.
- A high position or elevated status, especially in a figurative or social sense.
"The aircraft cruised at an altitude of 35,000 feet."
"The balloon ascended steadily until it reached an altitude of nearly 40 kilometres."
"After years of quiet work, she finally attained the altitude of her profession."
The plural is common when referring to different measured heights or a range of elevations, e.g. across a mountain range or during ascent.
"The survey recorded altitudes ranging from 200 to 3,000 metres across the valley."
At high altitudes, water boils at a lower temperature — which is why your tea goes cold faster on a mountaintop.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of altitude
Altitude derives from the Latin altitudo, a noun formed from altus, meaning 'high' or 'deep'. The word entered English in the late medieval or early modern period, likely through learned Latin usage, and became firmly established as scientific measurement of heights developed in the seventeenth and eighteenth centuries. It shares this Latin root with related terms such as exalt (to raise up) and alto (a voice part or musical register named for its height).
How altitude is actually used
In aviation and meteorology, altitude is measured against standard reference levels (sea level or a standard pressure datum), and units differ by region: feet are customary in US aviation, metres elsewhere. The figurative sense is less common and appears mostly in literary or rhetorical contexts.
Easily confused with altitude
Latitude measures angular distance north or south of the equator, whereas altitude measures vertical height above a reference level such as sea level.
Elevation typically refers to the height of a point on the Earth's surface above sea level, while altitude more often describes the height of an object (such as an aircraft) above that surface or above sea level.