It seems like a combination of two words:
* Mono: This is a slang term in Spanish meaning "bored" or "uninterested."
* Comb: This is the English word for the tool used to style hair.
Therefore, "mono comb" doesn't have a literal meaning. It's possible it's a slang term or a playful expression, perhaps referring to someone who is so bored they are picking at their hair with a comb.
Without more context, it's difficult to give a precise translation.