Starting with the Latin mea domina (my mistress), we progress through French ( ma dame or madame for Mrs.), to English madam, ma’am, mum, and sometimes even just – m (as in Yes’m).
So, what is grammaticalization? Roughly speaking, it is the series of steps by which collections of individual words that refer to objects and actions gradually mutate into complex systems of grammar, with pronouns, prepositions, conjunctions, verb endings, agreement, and so on. The steps operate on words (or, more broadly, multiword constructions) one at a time, and they follow a (roughly) predictable sequence with a fixed direction. It is from the sum of these changes, and their interactions, that the complexity of language spontaneously arises.
When we face new communicative challenges, we retain the ability to be tremendously inventive—including the ability to rework and repurpose the conventions we’ve already established.
With charades in mind, consider how we might expect this to work. First, and most obviously, if we communicate the same message repeatedly, the signal will become ever more simplified and standardized. In language, we see a relentless tendency to simplify, standardize, and throw away unnecessary complexity, provided that the message is still understood. Simplification over time leads to what is known as “erosion.” So, in English, going to becomes gonna; did not becomes didn’t; and over longer periods of time, erosion can be far more dramatic. Starting with the Latin mea domina (my mistress), we progress through French ( ma dame or madame for Mrs.), to English madam, ma’am, mum, and sometimes even just – m (as in Yes’m). Relatedly, erosion collapses forms with communicatively inessential differences. Contrast Early Modern English (the language of Shakespeare and the King James Bible) and Modern English: