katxo = box (noun) (some things Google found for "katxo": an uncommon to rare term; user names; a rare last name or first name that may be Basque; a Basque term for a fish which is probably the Iberian chub)
Word derivation for "box" :
Basque = kaxa (or kutxa), Finnish = laatikko
Miresua = katxo
Today in the UK and Canada is Boxing Day.