Compared with the form fathers, the word father is the older form of the two. The word father is a word current in this the nineteenth century. The same word was current in
the first century, although under a different form, and in a different language. Thus, in the Latin language, the form was pater; and earlier still, there is the Sanskrit form pitr. Now, just as the word father, compared with fathers, is original and primitive, so is pater, compared with father, original and primitive. The difference is, that in respect to father and fathers, the change that takes place, takes place within the same language, whilst the change that takes place between pater and father takes place within different languages. Of changes of this latter kind it is the province of etymology to take cognizance.
In its widest signification, etymology takes cognizance of the changes of the form of words. However, as the etymology that compares the forms fathers and father is different from the etymology that compares father and pater, we have, of etymology, two sorts: one dealing with the changes of form that words undergo in one and the same language (father, fathers), the other dealing with the changes that words undergo in passing from one language to another (pater, father).
The first of these sorts may be called etymology in the limited sense of the word, or the etymology of the grammarian. In this case it is opposed to orthoepy, orthography, syntax, and the other parts of grammar. This is the etymology of the ensuing pages.
The second may be called etymology in the wide sense of the word, historical etymology, or comparative etymology.
It must be again repeated that the two sorts of etymology agree in one point, viz., in taking cognizance of the changes of form that words undergo. Whether the change arise from grammatical reasons, as father, fathers, or from a change of language taking place in the lapse of time, as pater, father, is a matter of indifference.
In the Latin pater, and in the English father, we have one of two things, either two words descended or derived from each other, or two words descended or derived from a common original source.
In fathers we have a formation deduced from the radical word father.
In fatherlike we have a compound word capable of being analysed into the two primitive words, 1. father; 2. like.