Endlessly casting about, catching high-class marine creature

Wikipedia Word definitions in Wikipedia
A sea urchin is a spiny marine echinoderm. "Sea urchin" may also refer to: The Sea Urchin (1913 film) The Sea Urchin (1926 film) The Sea Urchins , an English indie pop band (1986–1991) Sea Urchins , a New Zealand television series (1980–84)

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Sea urchin \Sea" ur"chin\ (Zo["o]l.) Any one of numerous species of echinoderms of the order Echinoidea . Note: When living they are covered with movable spines which are often long and sharp.

WordNet Word definitions in WordNet
n. shallow-water echinoderms having soft bodies enclosed in thin spiny globular shells

Wiktionary Word definitions in Wiktionary
n. Any of many marine echinoderms, of the class ''Echinoidea'', commonly found in shallow water, having a complex chewing structure named Aristotle's lantern.

Longman Dictionary of Contemporary English Word definitions in Longman Dictionary of Contemporary English
noun EXAMPLES FROM CORPUS ▪ But please, hold the sea urchin . ▪ Oyster soup with sliced sea urchin is the other original Loiseau signature dish. ▪ Thousands of fertilized sea urchin eggs, starfish and blue clams returned to Earth with the astronauts.