Definition of slammer noun from the Oxford Advanced American Dictionary
slammer
noun
/ˈslæmər/
1the slammer[singular] (slang) prisonHe'll end up in the slammer one day.2[countable] (alsotequila slammer)an alcoholic drink made by mixing tequila and lemonade, that is drunk quickly after covering the glass and hitting it on the table to make the drink fill with bubbles