Eighth — Cannabis Slang Definition

An eighth is one-eighth of an ounce — 3.5 grams. The most common retail purchase size at U.S. dispensaries, and the baseline unit of American cannabis measurement.

Last verified: April 2026

Definition

An eighth is one-eighth of an ounce of cannabis — approximately 3.5 grams (more precisely, 3.54 g). At U.S. dispensaries, the eighth is the most common retail size: large enough to justify premium pricing and dedicated packaging, small enough for moderate consumers to finish in a reasonable window.

Etymology & Origin

The nomenclature descends from the American imperial ounce-based system, which has ruled U.S. cannabis commerce from prohibition onward despite the rest of the scientific world using grams. The cascading fractions — ounce, half-ounce, quarter-ounce, eighth-ounce, sixteenth-ounce (a “sixteenth” or “teenth”), and single gram — became the underground price ladder through the 1960s and 1970s. The imperial units stuck even as dispensary software could easily price in grams, because consumers knew the tiers and dealers had always used them.

Other common quantities: a quarter = 7 g, a half = 14 g, an ounce (O, zip) = 28 g, a pound (QP = quarter-pound). Some states cap single-transaction purchases at one ounce (California) or two and a half ounces (Michigan recreational). Medical cardholders often have higher limits.

Usage

  • “I’ll take an eighth of the Wedding Cake.”
  • “Eighths are on sale — $25 each, limit two.”
  • “An eighth lasts me about ten days.”

Pricing note: in the mature legal markets of 2026, eighth pricing typically runs $25-$50 at dispensaries, with the bottom tier shading into mids and the top tier into craft and small-batch. At 2010-era underground prices, eighths commonly ran $50-$65 — legal markets have lowered the price floor significantly.

Related Terms

See fire, mids, and the dispensary etiquette guide.