Under-stroke

Question

Yesterday a woman dictated the e-mail address of her company to me over the telephone. Between two of the words she inserted another word I didn't recognize. I finally figured out that she meant "under-stroke" but now I've forgotten the word she used. The spanishdict translator is no help. Does anybody know how to say "under-stroke" in Spanish? I'm in Mexico, if that matters.

Example: [e-mail]

Answer 1

http://www.ascii.cl/es/codigos-html.htm

According to this it is ASCII 95-

signo de subrayado

per Wiki:

http://es.wikipedia.org/wiki/Guion_bajo

El guion bajo [ _ ], también denominado subguión, subraya o barra baja, y conocido asimismo por el término en inglés underscore, es un carácter que se usaba en las máquinas de escribir para subrayar palabras.

Do any of these sound like what she used?

(sub) guión (bajo) is common in Mexico - 005faa61, Oct 3, 2014