The Spanish word 'hamaca' comes directly from the Taíno word 'hamaka', meaning 'hammock'. Taíno was the principal language of the indigenous peoples of the Caribbean when Spanish explorers first arrived in the Americas. This is one of many words that Spanish borrowed from indigenous American languages during the period of colonization.

Since 'hamaca' comes from Taíno rather than Latin or Greek roots, there aren't many etymologically related Spanish words. However, you might encounter the diminutive form 'hamaquita' (little hammock) or the related term 'hamaquero' (a hammock stand or someone who makes/sells hammocks).

The English word 'hammock' is actually related to Spanish 'hamaca', as both come from the same Taíno source word 'hamaka'. English borrowed this word through Spanish colonial vocabulary. This is a great example of how some English words came into the language through Spanish contact with indigenous American cultures.