‘鸭子’ (yā zi) literally combines ‘鸭’ (yā), meaning ‘duck’, and the diminutive or nominalizing suffix ‘子’ (zi). While ‘鸭’ alone is the standard, neutral term for ‘duck’, adding ‘子’ makes it more colloquial, familiar, and often child-friendly — similar to saying ‘duckie’ in English. It’s commonly used in everyday speech, storytelling, children’s books, and casual conversation, especially when referring to live ducks or evoking a sense of cuteness or informality.

The suffix ‘子’ here doesn’t change the core meaning but softens the tone; it’s rarely used in formal writing, scientific contexts, or culinary terminology (where ‘鸭’ or ‘鸭肉’ is preferred). ‘鸭子’ can also appear idiomatically — for example, in the phrase ‘鸭子听雷’ (a duck listening to thunder), meaning someone completely fails to understand something — though this is figurative and less common in daily use.