granny gear
noun
1
tranquillizers and anti-depressants, such as Valium™, Prozac™ and Rohypnol™. Drugs intended for GRANNY (an old woman), or intended to slow you down which is a stereotypical characteristic of a grandmother UK, 2005.
2
a car, truck, or bicycle's lowest gear; in a four-wheel drive automobile, the lowest gear combined with the lowest range in the transfer case US, 1993