Umlaut
You replace a vowel in the word stem with a different vowel, as in
sing - sang, or German
Haus - Häuser. A Gaelic example would be
bòrd - bùird or
fear - fir.
Palatalization/Slenderization
English does not use this means, but Gaelic does. One speaks of "palatalization of the final consonant", or simply of "slenderization". Example:
balach (boy) -
balaich (boys), [x] - [ç]. In some cases, this also works the other way around, e.g. the Genitive of
màthair (mother) is
màthar, [ɾʲ] - [ɾ]. Slenderization is marked orthographically by adding an < i> before the consonant. Note that the Gaelic umlaut examples I gave also have slenderization.
Initial Consonant Mutation
Initial consonant mutation means that the first consonant of a word changes. This seems very strange to us at first and takes some getting used to, so let me elaborate a bit. The origins of this process lie in the way the words run together in Gaelic. So, phonological rules that apply in the middle of a word also apply between the end of one word and the beginning of the next. Therefore, how the initial sound of a word is pronounced (in formal terms, which allophone is selected for the phoneme), also depends on the final sound in the preceding word. But what happens when the sounds at the end of words change? The reason for the change of the initial sound is gone, but the change can remain. If this happens with a consonant, we get initial consonant mutation, often simply called "mutation". This can take various forms, depending on what phonological rules originally applied. In Scottish Gaelic, there is only one form, and it's commonly termed as
lenition, as it's felt like a lightening of the sound. Often, you can also see the term "aspiration" being used for lenition. This is not to be confused with aspiration as we know it from
Lesson 4, which is why I will always say "lenition". In Gaelic, lenition is marked by adding an <h> behind the consonant that is lenited. Unfortunately, the lenition of l, n and r is not marked orthographically in modern spelling.
Example:
Feasgar math (good evening,
feasgar is a masculine noun, so you get [mah]) vs.
madainn mhath (good morning,
madainn is a feminine word, so you get [vãh]).
To compare with a language that will be more familiar to most of you, let's have a look at French
liaison: The plural "les" is pronounced without final -s in "
les maisons", but when you say "
les amis", you suddenly add a [z] for the -s. Actually, this [z] starts the first syllable in "
amis", so it has shifted over. Now, since romance languages took Latin as their role model, the changing of sounds at the beginning of words has always been frowned upon by those who made the norms. If the norm hadn't resisted these processes, we actually might have initial consonant mutation in modern French! Now, what happened in Gaelic is that Old Irish, which functions as the role model for the Celtic languages, is 800 years younger than classical Latin, and these changes had already happened then. Thus, mutation has always been part of the norm in the surviving Celtic languages. You can read more about the origins of lenition in
Lenition and why that is your mothers fault @ akerbeltz.
Suppletion
You replace a word by something completely different. e.g.
go - went. A Gaelic example would be the genitive of
bean (woman), which is
mnaoi.
Affixation
Just like in English, one way of forming the plural is by adding a suffix. In Gaelic, one of these is -
an, as in
cànan (language) -
cànanan (languages). Prefixation is rather used in word formation, as in
mì- +
fortanach =
mì-fhortanach (unlucky).
Reduplication
In reduplication, you repeat a word or part of a word. Example:
Tha e math math (It is good good = good indeed).