To take multiple consecutive bong hits, the duration of which can include an entire evening. This indubitably results in the transition of the participant from sophisticated scholar to paralysed imbecile.
Stoner A: "Has Liam been cramming for his test? I haven't seen him in bare time!"
Stoner B: "Nope, he's been chonging again. I swear down, he will be gutted when he gets his results, man!"
Etymology: Using the last name of Tommy Chong (of Cheech and Chong fame) as a verb.