The Spanish word 'brujita' meaning 'little witch' comes from 'bruja' (witch) with the diminutive suffix '-ita'. The word 'bruja' itself evolved from Medieval Spanish 'bruxa', which can be traced back to the Proto-Celtic word '*brixta', meaning 'magic spell'. This Celtic origin is interesting as it shows the influence of Celtic peoples on the Iberian Peninsula in ancient times.

The most obvious related Spanish word is 'bruja' (witch), which is the base word from which 'brujita' is formed. The suffix '-ita' is a very common diminutive in Spanish that makes things smaller or cuter, so 'brujita' literally means 'little witch' or can be used affectionately as 'dear witch'.

While there aren't any common English words directly related to 'brujita' through the Celtic root '*brixta', English borrowed the concept of witchcraft and magic from different Germanic roots. However, English speakers might find it interesting that the Spanish 'bruja/brujita' comes from an ancient Celtic word for magic spells, showing how concepts of magic and witchcraft have deep roots in European languages.