Visually hidden

For instance text for screenreader users.

.visually-hidden
{
  position: absolute;
  overflow: hidden;
  height: 1px;
  width: 1px;
  padding: 0;
  margin: -1px;
  clip: rect(1px, 1px, 1px, 1px);
  clip-path: inset(50%);
  white-space: nowrap;
  word-wrap: normal;
}

Visually hidden could also be defined via

.visually-hidden:not(:focus):not(:active)

Sources:

• WebAIM
• Paciello Group
• Screen reader text Why and How
• CSS tricks