Folk etymology of Spanish 'cucaracha' — reshaped into 'cock' and 'roach,' neither related to the insect.
A flat-bodied nocturnal insect of the order Blattodea, typically brown or black, with long antennae and a reputation for infesting human dwellings.
From Spanish 'cucaracha' (cockroach), of uncertain ultimate origin, possibly from 'cuca' (a caterpillar or type of bug). The English form is a folk etymology: English speakers heard the unfamiliar Spanish word and reshaped it into two familiar English words — 'cock' (rooster) and 'roach' — neither of which has any connection to the insect. This process, called folk etymology, disguised the Spanish origin so effectively that most English speakers have no idea the word is borrowed. Key roots