Derived stems

Derived stems are a morphological feature of verbs common to the Semitic languages. These derived verb stems are sometimes called augmentations or forms of the verb, or are identified by their Hebrew name binyanim. Semitic languages make extensive use of nonconcatenative morphology, and most words share a set of two, three or four consonants which comprise a root wherein each root may be the basis for a number of conceptually related words. Traditionally, words are thought of as being derived from these root consonants, but a view increasingly held by contemporary linguists sees stem words being the source of derivations rather than consonantal roots. Regardless, each language features a number of set patterns for deriving verb stems from a given root or underived stem. Stems sharing the same root consonants represent separate verbs, albeit often semantically related, and each is the basis for its own conjugational paradigm. As a result, these derived stems are part of the system of derivational morphology, not part of the inflectional system.

Typically, one stem is associated with the ordinary simple active verbs while others may be canonically associated with other grammatical functions such as the passive, the causative, the intensive, the reflexive, etc., or combinations thereof. These functions should not be taken as universal or absolute, but are better understood as relational, depending on the particular source of the derived stem. These grammatical functions are also not present in all Semitic languages, Modern Aramaic, for example has only two stems, one for monosyllabic verbs and the other for disyllabic verbs, with hardly any cases of related verbs in each stem.

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