A sexual/alcohol-related act akin to the infamous buttchug. When performing a Mexican Dipstick, one party will soak their finger in tequila, and gently insert it into the anus of the other party.

Note: the salt on the rim is optional, but recommended.
I was hoping to party but all I had was tequila. Hating the taste, I asked my lover to perform a Mexican Dipstick, hold the salt.
by Year of the Browneye February 14, 2016
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A knife. Termed "Mexican Dipstick" due to the amount of Mexicans (mainly those in gangs) who typically wield knives.
Primary function is to determine if the person it is tested on (victim) is low on oil (blood). A play on the "real" dipstick, used to measure oil.
So I was walking to the 7-11 and some guy was like "Tennis Rules!" so I responded with "Tennis is for bitches!". He proceded to pull out his mexican dipstick and chase me for 2 blocks before he gave up.
by Teh Lolly Roffler August 5, 2007
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