Princeton's WordNet(3.00 / 1 vote)Rate this definition: 1  opacity(noun) the phenomenon of not permitting the passage of electromagnetic radiation. 2  opacity, opaqueness(noun) incomprehensibility resulting from obscurity of meaning.
The Oystercatcher is a species of bird that lives around Europe and Asia. They usually eat shellfishes that are found on beaches and mud.The Eurasian Oystercatcher uses its sharp bill to open the shells of oysters and mussels.It cuts the muscle between the two halves of the shell together, or it crashes the shell against a rock and eats the oyster inside.ith bills like that, oystercatchers are dangerous opponents for other birds. They can fight off predators, and often raid other birds to steal their catches. They attack other birds at an average of five-minute intervals during low tide. They get as much as 60% of their food by theft.
Definition of ratcatcher. 1  1 : a person or animal employed in exterminating rats. 2  2 chiefly British : informal hunting dress; especially : a tweed jacket with tan breeches.