Canaanite shift

In historical linguistics, the Canaanite shift is a sound change that took place in the Canaanite dialects, which belong to the Northwest Semitic branch of the Semitic languages family. This sound change caused Proto-NW-Semitic *ā (long a) to turn into ō (long o) in Proto-Canaanite. It accounts, for example, for the difference between the second vowel of Hebrew (šalom, Tiberian šālōm) and its Arabic cognate (salām). The original word was probably *šalām-, with the ā preserved in Arabic, but transformed into ō in Hebrew. The change is attested in records from the Amarna period, dating it to the mid-2nd millennium BCE.

This vowel shift is well attested in Hebrew and other Canaanite languages, but its exact nature is unclear and contested.

Many scholars consider this shift to be unconditioned. This position states that there were no conditioning factors such as stress or surrounding consonants which affected whether or not any given Proto-Semitic *ā became ō in Canaanite. Such scholars point to the fact that Proto-Semitic *ā virtually always reflects as ō in Hebrew.

Some other scholars point to Hebrew words like שמאלי səmālī (an adjective meaning "on the left"), in which the original *ā is thought to be preserved. Since such a preservation would be hard to explain by secondary processes like borrowing or analogy, they often assume that the shift was conditional and took place only in stressed syllables and that later, many words changed their form in analogy to other words in the same paradigm. As a result, the conditional nature of the shift became indistinct.

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