Which term describes a dog that is not friendly around people or socialized pets?

The term that accurately describes a dog that is not friendly around people or socialized pets is "asocial." An asocial dog tends to avoid interactions with others, whether they are humans or other animals. This behavior may stem from a lack of socialization or positive experiences with people and animals during critical developmental periods. Understanding this term is important for recognizing and addressing behavioral issues in dogs, particularly in training and rehabilitation contexts.

The other terms offer different meanings that do not align with the characteristics described in the question. For instance, an affectionate dog tends to express warmth and love toward people and other pets, while a playful dog seeks interaction through games and activities. A timid dog, on the other hand, might be shy or fearful but does not necessarily possess the same avoidance characteristics as an asocial dog. By understanding these distinctions, one can better identify and manage canine behavior in various social situations.