Language & WorldFact
About 4,000 Spanish words are actually Arabic.
Nearly 800 years of Muslim rule on the Iberian Peninsula (711 to 1492) left around 4,000 words in Spanish. A tell-tale sign is a fused Arabic article 'al-': almohada (pillow), alcalde (mayor), algodón (cotton), azúcar (sugar), aceite (oil). Place names like Guadalquivir ('the great river') are Arabic too.
Useful: If a Spanish word starts with 'al-' or 'a-' plus a consonant, odds are good it's Arabic.
Source: en.wikipedia.org