Combining Left Arrow Above

It puts a left-pointing arrow above the preceding symbol.

Its useful setting is mathematical notation: an overhead arrow can mark a directed quantity, especially a vector—a value with size and direction. This arrow supplies a leftward direction cue.

Vector notation has roots in nineteenth century mathematical work; historical accounts place most basic vector and matrix notation by the early twentieth century. An overhead arrow is one convention among several: bold type, Gothic or blackletter-style letters, and other styles can distinguish vectors from scalars, quantities with size but no direction. Unicode groups this mark with combining arrows for rotation, harpoons, and arrows pointing other ways; each marks a different direction or shape.

How do I type a left arrow above a letter?

Put the base character first, then append the combining mark.

The sequence is base followed by U+20D6: x⃖. The mark modifies the preceding base; by itself it is not a standalone left arrow. In HTML, ⃖ after the base is the character reference. In LaTeX, \overleftarrow{x} makes a stretchable arrow over x.

Why does the arrow render in the wrong place?

Fonts and math renderers handle combining marks inconsistently.

A font may lack the mark or have poor combining-mark spacing, leaving the arrow too high or low, detached, or invisible. That is a layout problem; it does not change which character follows the base.

For a long vector name or expression, use a stretchy math accent such as \overleftarrow{...}. One combining mark is not a reliable way to span several characters.