Interfix

Interfix, or, more commonly, linking element, is a term in linguistics and more specifically, phonology. It describes a phoneme which is placed in between two morphemes and does not have a semantic meaning.

In German, the interfix -s- has to be used between certain nouns in compound words, but not all, such as Arbeitszimmer ("workroom") as opposed to Schlafzimmer ("bedroom"). This originates from the masculine and neuter genitive singular suffix -s. German has many other interfixes, for example -es, -(e)n-, -er- and -e-. Not all of them originate from the genitive. Likewise, it is often stated that German interfixes originated from plural forms, when in fact German plural forms and linking forms developed parallel to each other and are only partly similar by coincidence.

In English, when technical compound words are formed from non-technical roots, an -o- interfix is sometimes used, as o has come to be seen as a connecting vowel (speed-o-meter, mile-o-meter) by analogy to tacho-meter, odo-meter, compounds of which the first part comes from an Ancient Greek noun whose stem includes o.

In Swedish, compound nouns are written as one word, and interfixes are very common. -s- is frequently used in this way, as in fabriksarbetare, which consists of fabrik (factory) and arbetare (worker). Examples of other interfixes are -e-, as in when familj and far (family and father) become familjefar, and -a-, when viking and by (viking and village) become vikingaby. However, just like in Norwegian, not all compound words are written with an interfix. For example stenålder, which consists of sten (stone) and ålder (age). Some words ending in a vowel lose the last letter. For example arbetarklass (working class) consists of arbetare (worker) and klass (class).

Norwegian is closely related to Swedish and has a similar pattern, but uses interfixing somewhat more moderately. Examples: "arbeid" + "rom" = "arbeidsrom" (workroom), but "fabrikk" + "arbeider" = "fabrikkarbeider" and "familie" + "far" = "familiefar". The most common interfix is -s-, but there are examples with -e-: "barn" + "hage" = "barnehage" (kindergarten), and "bjørn" + "hi" = "bjørnehi" (bear hive / bear's nest).

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