The Merrow, also known as the Muireartach or Murdúch, is a mythical creature in Irish and Scottish folklore. It is often considered a type of mermaid or merfolk, but with distinct characteristics unique to Celtic mythology. Merrows are typically depicted as having a human-like upper body and a fish-like lower body. They have the appearance of a traditional mermaid or merman. The tail is often described as being covered in shimmering scales.

"Illustration of a Merrow, an Irish mermaid, beneath the sea waves

Physical characteristics

Upper Humanoid Body: The upper part of the Merrow’s body resembles that of a human. This includes the torso, arms, and head.

Fish-Like Lower Body: The lower part of the Merrow’s body is depicted as fish-like, with a scaly tail instead of legs.

Webbed Hands: Merrows are often described as having webbed fingers.

Shimmering Scales: The scales covering the Merrow’s fish-like tail are often described as shimmering or iridescent.

Green Hair: Merrows are commonly portrayed with long, flowing green hair.

Red Cap: The Merrow is often associated with wearing a magical red cap. This cap is considered a source of their supernatural powers, and losing it can have consequences for the Merrow.


The word “Merrow” itself is believed to be derived from the Irish and Scottish Gaelic words “muir,” meaning sea, and “oigh,” meaning maid or young girl. Thus, the term can be translated as “maid of the sea” or “sea maiden.”

The specific characteristics and stories about Merrows can vary across regions and communities, but common themes include their enchanting singing, romantic entanglements with humans, and the mystical properties of their red caps.

Merrow caught in a moment of solitude under the ocean's surface

powers and abilities

Enchanting Singing: Merrows are renowned for their captivating and enchanting singing voices.

Shapeshifting: Merrows are believed to have the ability to shape-shift. They can transform from their mermaid or merman form into that of a seal.

Magical Red Cap: The Merrow’s red cap is considered a source of its magical powers. It is said to allow them to return to the sea and transform into a seal. Losing the cap can result in the Merrow losing its ability to return to its aquatic home.

Weather Manipulation: Merrows are associated with the power to influence weather conditions, particularly storms at sea.

Healing Powers: In certain tales, Merrows are attributed with healing abilities. Their touch or presence is believed to have therapeutic effects.

Ability to Control Tides: In some variations, Merrows are said to have the ability to control the tides, influencing the ebb and flow of the ocean.

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