|escape character (\)|
|Definition - One of the many names for the \ symbol.|
Etymology - The term escape character arose from the field of computing science in the latter half of the 20th century. In that field, it denotes a code used to indicate that subsequence characters should be interpreted differently.
Oxford English Dictionary - The phrase's first citation is from 1962:
"*Escape character, a character used to indicate that the digit which follows is to be interpreted as belonging to a different alphabet."
(Gloss. Terms Automatic Data Processing (B.S.I.) 15)