In German, alt means old, so, for example, altschuler means old school.
In usenet, alt means alternate.
In US English, alt means high or deep, as in altimeter.
On a keyboard, alt means hold down the ALT key while pressing another key.
There are probably many more meanings of the prefix alt.
prefix
High, deep.
The prefix "alt" typically means alternative or alternate. It is used to indicate a different or substitute option, as in words like "alternative," "alternate," or "altercation."
what is the prefix meaning of in
the prefix for unlike is -un
The prefix meaning foreign is "exo-".
The prefix meaning height is Acro-
One who lusts., Alt. of Lustre, Alt. of Lustre
prefix
The prefix meaning "billion" is "giga-".
prefix meaning fast
"Neo-" is a prefix meaning modern.