Feminine and masculine designations : what is derived from what?

Answer

In this interesting question, you bring together several principles.

The basic principle is that every natural language is built as a binary structure (like a digital system) with one element marked and the other unmarked. The linguistic concept of “gender” in the cases you cite consists of two members: masculine and feminine. In Dutch as in most languages ​​we are familiar with, the masculine is considered the “gender” “by default”, so the masculine is not marked. In other words, it will also be used when we do not wish to specify the gender (eg man is mortal, someone, etc…). This implies that female is marked for the gender. This in turn means that the marked form also takes on a special form in the coding of the language (in the forms the language uses to express messages). By definition, therefore, the feminine form is more complex than the masculine: it is derived from the masculine, because it is marked.

The two exceptions you give are different in nature.

With cat and tomcat you start from the generic word “cat”. Cat refers to the species, not specifically to the female cat. With animal names it more often happens (in almost all languages) that the noun has its own gender, irrespective of the sex of the animal: the snake, the spider, the okapi have a certain grammatical gender, but the word refers to the species, not to a natural sex. Such words are called epicenes. In that case, one will have to add the adjectives male or female to indicate the gender: a female/male okapi, for example. The word cat also refers to the species. But because cat as a generic name in Dutch is of the female gender, it can also be used to refer to a cat of the female gender. So hangover is in fact derived from the generic word cat. Southern Dutch, on the other hand, has a derivation for both sexes: kater for the male animal and kattin for the female. According to the language variant, one can therefore use kat or kattin for the female animal.

Widow probably follows another principle, that of the frequency we encounter in a given society. Instead of the binary principle unmarked / marked, the principle of frequency can apply in a language. In that case, the most frequent concept is the basis and the derivative is based on the most common. Consider, for example, a midwife.