• abbreviation
• back-formation
• blend
• context of use
• infixation
• phonaestheme
• reduplication

The analysis conducted in this work intends to make a contribution to the debate on the position that extra-grammatical processes occupy within English morphology with respect to that of grammatical ones. It represents an attempt to explore in detail and describe English extra-grammatical operations which are nowadays frequently and productively used in Modern English.
In particular, chapter 1 is an introduction on the main theories which are relevant in order to draw a clear definition of extra-grammaticality. Chapter 2 introduces the extra-grammatical process of abbreviations, distinguishing between three phenomena, namely, clippings, acronyms and initialisms. Chapter 3 and 4 deal respectively with the extra-grammatical phenomena of blending and reduplication. Chapter 5 investigates the so-called ‘marginal phenomena’, i.e. those processes which are considered of minor importance, because less productive and used than others, e.g. back-formation, infixation and phonaesthemes. Chapter 6 is devoted to the contextualization of all types of extra-grammatical formations within different contexts of use, in order to confirm the widespread creation and use of these new formations. In this specific case, we analyze extra-grammatical phenomena according to three fundamental principles, i.e. the principle of informality, economy and naming.