Perhaps self-explanatory, an eighth is one-eighth of one ounce of marijuana. A pretty hard-core stoner friend of mine says that the stoner community considers an eighth to be a pretty small amount of dope. An eighth may be the smallest amount that a drug dealer traffics in. An eighth of quite good stuff runs about $50-$60.

Usually, however, what is labelled an 'eighth' is actually around 3.5 grams.

See pot jargon metanode or drug slang metanode for other units of pot-selling.