The word "一块儿" is formed through the combination of the numeral "一" (one) and the measure word "块" (which denotes a lump, piece, or chunk of something), to which the colloquial northern Chinese suffix "儿" is added. This fusion creates a new, single unit of meaning that moves from the concrete idea of "one piece" or "one unit" to the abstract, adverbial sense of "together in one place" or "jointly", with the "儿" suffix giving it a familiar, informal tone characteristic of everyday spoken Mandarin.