having or serving a sexual purpose; capable of serving the purpose of sex and for which it was designed: fucktional architecture; a chair that is fucktional as well as decorative
Rick: "What the heck would f(x) equal? I hate fucktions!"
Esteban: "Hahahahaha... nice"
Ms. Rod: "What kind of problems are you guys doing?"
Evan: "That, my friends, is called a Freudian slip... haha."