Canaanite term for Jericho

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Jericho's name in Modern Hebrew, Yeriẖo, is generally thought to derive from the Canaanite word rēḥ 'fragrant', but other theories hold that it originates in the Canaanite word Yaraḥ 'moon' or the name of the lunar deity Yarikh, for whom the city was an early centre of worship.^[19]

Jericho's Arabic name, Arīḥā, means 'fragrant' and also has its roots in Canaanite Reaẖ,

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The etymology of Jericho and its historical names offer a fascinating glimpse into the city's long history:

Etymology:

• The prevailing theory suggests Jericho's name originates from the Canaanite word "rēḥ" which translates to "fragrant". This could be a reference to the city's fertile oasis environment or the use of fragrant plants in religious ceremonies.
• Alternative theories propose the name might come from the Canaanite word "Yaraḥ" meaning "moon" or the name of the moon deity "Yarikh". This theory aligns with archaeological evidence suggesting an early moon cult existed in the city.

Historical Names:

• The city's name in modern Hebrew is "Yeriẖo", reflecting its Canaanite roots.
• The biblical Hebrew name was "Yeriḥō", appearing numerous times in the Old Testament.
• The Arabic name is "Arīḥā", directly related to the Canaanite word "rēḥ", signifying "fragrant."
• In ancient Greek texts, Jericho was referred to as "Ἱερῑχώ" (Ierīkhṓ)", which transliterates the Hebrew name.
• During periods of Roman and Byzantine rule, the city was known as "Hiericous" or "Hierichus", derived from the Greek name.
• Early Arabic sources sometimes referred to Jericho as "Riḥā", a simpler form of the modern Arabic name.

Therefore, understanding the etymology and historical names of Jericho allows us to appreciate its long and continuous legacy, spanning various linguistic and cultural contexts.

As for Hebrew and Arabic being related languages, again Wikipedia provides the answer Semitic languages - Wikipedia.