mobility
- 1The ability to move, or the general capacity for movement of a body or person.
The injury left him with limited mobility in his right knee.
Wheelchairs and ramps give people greater mobility in public spaces.
Similarmovement, motion, maneuverability
Oppositeimmobility
Note
This is the everyday sense, carried into English from Middle French mobilité and its Latin source mobilitas. It can describe a single body, as when Hadley Freeman sets high heels against women's mobility. It can also describe a whole population on the move: an Edwardian Christmas was "a period of great mobility" because people traveled. When the body is meant, limited and greater are natural companions.
- 2The capacity of people to change their social class or move from one occupation to another.
Sociologists often treat education as a key driver of upward mobility.
Rigid class structures can severely limit mobility across generations.
Note
Sociologists track this movement within a single lifetime and across generations, and the word rarely stands alone. It usually comes qualified: upward mobility, social mobility, a decline in mobility. Thomas B. Edsall, writing in 2020, pictured it as rising up the economic ladder and found the frustration over its decline in the United States sharpest among those without college degrees.
- 3A military unit's ability to move or be transported to a new position.
Light infantry units prize mobility over heavy armor.
The general improved his force's mobility by securing more transport aircraft.
Similarmaneuverability, agility
Note
Armies reckon it in vehicles, terrain and supply. A unit is only as mobile as the transport, ground and supply lines that carry it, and that capacity sets the tempo of operations. It is a planner's word, often weighed against protection, as when light infantry give up heavy armor to gain it.
- 4The amount of motion among the particles that make up a liquid or gas.
As temperature rises, the mobility of gas molecules increases sharply.
The high mobility of particles in a gas explains why it spreads to fill a container.
Note
Physics turns the word into a quantity: it measures how freely particles move and diffuse through the medium around them. Because it is a degree rather than a yes-or-no ability, it is compared and qualified freely. Writers speak of high mobility, low mobility, or mobility that rises with temperature.
- 5A tendency toward sudden change; changeableness or mutability.
The poem captures the mobility of the human heart, forever changing its loyalties.
Critics praised the novel for showing the mobility of fortune within a single family.
Similarchangeability, mutability, fickleness, inconstancy, volatility
Oppositeconstancy, stability, steadfastness
Note
Here the movement is of mood and fortune rather than of the body, and the word belongs to literary writing. A poet or novelist may speak of the mobility of a heart or of fortune. In ordinary prose, changeableness or mutability says the same thing more plainly, and they avoid any risk of the reader hearing the physical sense instead.
Practice
Can you tell the meanings of mobility apart? Answer 3 quick questions from this page, or write your own sentence and AI will check it.
Origin
From Middle French mobilité, which came from Latin mōbilitās, meaning 'mobility'.