The Spanish word 'roca' meaning 'rock' comes directly from Late Latin 'rocca' with the same meaning. The word maintained both its form and meaning quite closely as it evolved from Late Latin into Spanish, with just a simplification of the double 'c' to a single 'c'.

Some related Spanish words include 'roquero' (meaning 'rocky' or 'rock musician'), 'enrocar' (to fortify with rocks), and 'rocoso' (rocky). These words are all built from the base word 'roca' and extend its meaning in logical ways.

While English 'rock' might seem related to Spanish 'roca', they actually have different etymological origins. However, English has borrowed some words from the same Latin root, such as 'rococo' (an ornate artistic style named after rocks and shells) and 'rockery' (a garden feature made with rocks). The word has also influenced English through French in words like 'roche' and 'rochelle'.