Motivation and semantic change

The history of the noun deer is essentially the same. In Old English deor it had a general meaning denoting any beast. In that meaning it collided with the borrowed word animal and changed its meaning to the modern one ("a certain kind of beast", R. олень).

• The history of the noun deer is essentially the same. In Old English deor it had a general meaning denoting any beast. In that meaning it collided with the borrowed word animal and changed its meaning to the modern one ("a certain kind of beast", R. олень).
• The noun knave (О. Е. knafa) suffered an even more striking change of meaning as a result of collision with its synonym boy. Now it has a pronounced negative evaluative connotation and means "swindler, scoundrel".