Pet-names and the OED

IT has often been observed that the names given to pets and other animals show a striking level of fluidity, proving uniquely capable of drifting between the specific and the generic. Over time, when proper nouns are linked by convention to particular types of creature, they often broaden into general labels for that creature, coming to denote genders, breeds, or even entire species of animal. English contains several terms that have expanded in this way during their history: examples include such colloquial designations as ‘moggy’ or ‘dobbin’, compounds such as ‘jenny wren’ or ‘jackass’, and even terms that have managed to displace the original species name altogether, such as ‘robin’, which overtook the earlier ‘redbreast’ during the late sixteenth century. Nevertheless, it can often be difficult to identify the point at which an animal name has undergone this widening. For this reason, there are a number of instances where the OED assigns too late a date for the emergence of these curious terms. Some of these problematic entries are listed below, with a number of witnesses predating the earliest examples currently given in the dictionary. [Opening paragraph]