Where sources for terms are known, these are given. This can lead to rather obscure or lengthy definitions, which you have permission to skip if you're not interested... Some of the more common ways that words arise will be discussed now.
Firstly, MUD players get quite fond of some of the inhabitants of the game, and give them pet names. These are normally generated by shortening the name a little and adding a 'y' or 'ie' at the end, as in 'draggy' for 'dragon'. Personae may have short nicknames, but they don't usually get the 'y' treatment.
MUD players are also acutely aware of gender, since most of them have personae of both sorts. They don't like referring generically to personae in a gender-specific fashion, especially when referring to experience levels, and therefore there have evolved three principal ways to reference personae of either sex. The most laborious approach is to separate the alternatives by a '/', eg. 'Sir/Lady'. Since that can be rather long and lead to pluralisation problems, sometimes the male form is given with the feminine suffix following the '/', eg. 'enchanter/ess'. This is still unwieldy, so further contraction can be applied to yield a gender-free term which can be used generically, eg. 'wiz' for 'witch/wizard'. It's mostly level names on the standard career path which undergo the full surgery, with the glaring exception of 'hero/ine' (for which a suitable derivative has yet to find favour).
As usual in highly-interactive communities, nouns are often used as verbs and verbs as nouns. 'To MUD' means 'to play MUD'; 'Can I have a restore?' means 'Can you restore my persona?'. There are examples of this practice throughout the dictionary.
Another common way that terms arise is by back-formation (eg. 'fangling' meaning 'that which is newfangled'), but this is comparatively rare among MUD players. This may be because back-formation extends a term, rather than foreshortening it. There is some over-generalisation, eg. forming 'baloonatic' from 'baloon', but, again, these occur less often than a linguist might at first expect from a slang language. The critical factor is the time it takes to type something, and when time is important then abbreviations and contractions reign. As MUD itself accepts a host of abbreviations covering pretty well everything you need (especially common verbs, nouns and prepositions), the practice is actively encouraged and becomes second-nature to the players; they sprinkle abbreviations, acronyms and contractions into their 'speech' with impunity, and may not even notice.
Finally, some words and phrases come from the actions or personality of individual players. These usages tend to be short-lived, disappearing when the player becomes inactive. Although 'how very Cynth' might have been meaningful to MUD1 players in 1982, it is only of minor historical interest now. In the long term, all persona names are transient: for this reason, and to avoid offending players whose names are overlooked, no name-derived terms are included in this dictionary. The names used in examples are not intended to carry any such significance. Some real-world names /are/ used, however, principally those of people historically associated with the actual development of MUD.