The Spanish word 'chamarra' meaning 'jacket' has an interesting origin that traces back to the Basque language. It comes from the Basque word 'zamar' which meant a 'covering garment'. This word entered Spanish as 'zamarra', specifically referring to a 'sheepskin jacket', before evolving into the modern form 'chamarra'. The change from 'z' to 'ch' is a common phonetic shift in Spanish, and the meaning broadened from specifically sheepskin jackets to jackets in general.

A closely related Spanish word is 'zamarra', which still specifically refers to a sheepskin jacket or coat. While 'chamarra' has become the more general term for any jacket, 'zamarra' maintains its specific connection to traditional sheepskin garments.

While there aren't any commonly used English words directly related to 'chamarra', English speakers might be interested to know that some traditional winter clothing terms in English also have origins in words for sheepskin garments, though from different linguistic sources.