Definitions

1. noun

a person, typically a young adult, who uses or abuses LSD, especially in the 1960s counterculture

“The artist’s acidhead experiences during the 1960s inspired some of her most iconic works.”

2. noun

a person who is excessively indulgent in or sensitive to acid or acidic substances

“The acidhead in the lab had to wear protective gear to handle the corrosive chemicals.”