半はん索さく動どう物ぶつ門もん

Meanings

1

Hemichordata; hemichordates

A phylum of marine deuterostome animals, including acorn worms and graptolites. Used in biological and taxonomic contexts.

gate, counter for cannons

脊せき索さく動どう物ぶつ門もん
Chordata, another deuterostome phylum that includes vertebrates, while Hemichordata is a separate phylum of worm-like marine organisms.
棘きょく皮ひ動どう物ぶつ門もん
Echinodermata, a sister phylum to hemichordates within the deuterostomes, including starfish and sea urchins.

From 半 (half) + 索 (cord) + 動物 (animal) + 門 (phylum), referring to the stomochord, a structure once thought to be a notochord-like cord.