Universals of language have been studied extensively for the last four decades, allowing fundamental insight into the principles and general properties of human language. Only incidentally have researchers looked at the other end of the scale. And even when they did, they mostly just noted peculiar facts as ''quirks'' or ''unusual behavior'', without making too much of an effort at explaining them beyond calling them ''exceptions'' to various rules or generalizations. Rarissima and rara, features and properties found only in one or very few languages, tell us as much about the capacities and limits of human language(s) as do universals. Explaining the existence of such rare phenomena on the one hand, and the fact of their rareness or uniqueness on the other, is a reasonable and interesting challenge to any theory of how human language works. The present volume for the first time compiles selected papers on the study of rare linguistic features from various fields of linguistics and from a wide range of languages.

The papers in this book describe and analyze rara in individual languages, covering an extraordinarily broad geographic distribution, including papers about languages from all over the globe. The range of theoretical subjects discussed shows an enormous breadth, ranging from phonology through word formation, lexical semantics to syntax and even some sociolinguistics.

The questions as to why most languages appear to have more trouble borrowing verbs than nouns, and as to the possible mechanisms and paths by which verbs can be borrowed or the obstacles for verb borrowing, have been a topic of interest since the late 19th century. However, no truly substantial typological research had been undertaken in this field before the present study. The present work is the first in-depth cross-linguistic study on loan verbs and the morphological, syntactic and sociolinguistic aspects of loan verb accommodation. It applies current methodologies on database management, quantitative analysis and typological conventions and it is based on a broad global sample of data from over 400 languages and the typological data from the World Atlas of Language Structures (WALS). One major result of the present study is the falsification, on empirical grounds, of long-standing claims that verbs generally are more difficult to borrow than other parts of speech, or that verbs could never be borrowed as verbs and always needed a re-verbalization in the borrowing language.