köken: Uncertain. Inherited from Old Spanish loco, perhaps from Andalusian Arabic لَوْقَاء (láwqa), from Arabic لَوْقَاء (lawqāʔ), feminine singular form of أَلْوَق (ʔalwaq, “stupid”), by reinterpreting the final Andalusian Arabic -a as the Ibero-Romance -a and back-forming the masculine with -o. Edward Roberts thinks the term is related to Arabic لَاق (lāq, “to soften”), but this verb is of root l-y-q,…