More than likely it meant the stuff on it was
optimized for a H1400
terminal (Hazeltine only made terminals).
I knew that, but try arguing with a customer about that. The
1400--one of the more awful, but cheap, terminals in the terminal
universe. For some odd reason, it used tilde (hex 7E) as the escape
lead-in character. I also seem to recall that attributes tood up a
space in the display, but I may have that confused with one of the
early Wyse displays.
H1400 was ANSI just like VT100 (in Vt100 mode) and many others. The
escape sequences were ANSI plus private (hazelitne additions).