Irish moss

Irish moss may refer to:

• Chondrus crispus, a commonly gathered seaweed; a clarifying agent in beer brewing
• Mastocarpus stellatus, a less commonly gathered seaweed
• Sagina subulata, a terrestrial plant with needle-like leaves
• Soleirolia soleirolii, a terrestrial plant with round leaves
• Arenaria verna, a terrestrial plant in the genus Arenaria
• Gracilaria, a genus of seaweed
• Irish moss (drink), a beverage in Jamaican cuisine made from Gracilaria
• Gelidium amansii, a genus of seaweed which yields agar agar