Mermaids are water spirits, and in Irish folklore, they’re known as Merrows. Mermaids are depicted as half-human, half-fish creatures and have been around for centuries in folklore and legends. Mermaids love music, and you’ll often hear them singing.
These water spirits have been linked to sorrow and destruction in modern and ancient folklore, while they can also be compassionate. They have provided the wisdom of natural remedies for deadly illnesses, lavish gifts, and storm advisories when rescued or saved. They may also lure sailors to doom and death by guiding them to rocks and causing their ships to wreck.
Mermen are sometimes associated with eating their own children or drowning people underwater out of spite and revenge for fishing in their territory.
Aquatic mammals, such as the dugong and manatee, that suckle their young in human fashion above water are considered by some to be the origin of myths about mermaids.
Britannica – Mermaid – Legendary being