Definitions for "Hard hyphen"
A hyphen at which line wrapping cannot occur. It ensures that the enclosing word remains on the same line should a line break be required anywhere within the word. In this case, the word is moved to the next line. See also: soft hyphen
Another term for nonbreaking hyphen. See NONBREAKING HYPHEN
In typography, a hyphen that is always typeset, regardless of where on the line it falls. Such a hyphen would be one of those in the word “mother-in-law”.