horse mackerel
noun
1.
bluefin tuna
.
2.
jack mackerel
.
Origin
1695-1705
British Dictionary definitions for
horse mackerel
horse mackerel
noun
1.
Also called
scad.
a mackerel-like carangid fish,
Trachurus
of European Atlantic waters, with a row of bony scales along the lateral line
Sometimes called (US)
saurel
2.
any of various large tunnies or related fishes