The Spanish verb 'centellear' (meaning 'to sparkle' or 'to flash') comes from the Spanish noun 'centella' meaning 'spark' or 'flash', combined with the verbal suffix '-ear'. The noun 'centella' itself derives from the Latin word 'scintilla', which also meant 'spark' or 'flash'. The transformation from Latin 'scintilla' to Spanish 'centella' shows some typical sound changes that occurred as Latin evolved into Spanish, including the shift of 'sc-' to 'c-' and the palatalization of '-ll-'.

A simpler related Spanish word is 'centella', which is the noun meaning 'spark' or 'flash'. This word is commonly used in expressions related to lightning or electrical sparks. The verb 'centellear' was formed from this noun to describe the action of producing sparks or flashing repeatedly.

The English word 'scintillate' is a cousin of 'centellear', as both derive from the Latin 'scintilla'. While Spanish developed 'centella' and 'centellear', English borrowed 'scintillate' directly from Latin, maintaining more of the original spelling. Both words share the core meaning of sparkling or flashing, though 'scintillate' in English has also developed the figurative meaning of being brilliantly clever or witty.