Tussocks dense. Leaves flat or slightly concavo-convex in cross-section, occasionally inrolled, (35–)50–100 cm long, 2–10 mm wide, glabrous; basal sheath gradually tapering distally, intact or coarsely torn, brown, orange-brown or reddish brown, occasionally white; apex (often irregularly) 2- or 3-pointed. Male and female inflorescences similar, unbranched or branched, the larger branches or all branches often 2 per node and distichous, 12–50 cm long, with flower clusters whorled; non-flowering axis exposed for 4.5–42 cm, laterally flattened; flower-bearing axis 4.5–30 cm long. Bracts at the base of each cluster of flowers generally longer to much longer than the flowers (rarely shorter than flower clusters or apparently absent), pungent, straw-coloured to whitish. Flowers sessile; outer perianth shiny, papery, purplish or yellow; inner perianth fleshy, yellow or cream-coloured. Male flowers 3–3.5 mm long; female flowers c. 4.5 mm long. Spiny-headed Mat-rush, Karawun (Koorie name).