The Spanish word "pinche", according to sources is an all-purpose insult enhancer, which would be roughly equivalent to the use of the F-word in English.
It is strongly associated with cursing which is not just isolated to Mexico. Reports say that people from Panama and Columbia also understand that it is used to describe something insignificant.
While "mayate" references a black dung beetle and is a derogatory term used to describe a dark skinned person.
Combining these two words then will give a very clear explanation of what they sadly imply.
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