linguistics

Linguistics was coined in 1847 by philosopher William Whewell from German Linguistik, formed as linguist plus the suffix -ics. Linguist itself traces back to Latin lingua, meaning tongue, via Proto-Italic and ultimately Proto-Indo-European *dn̥ǵʰwéh₂s.

The word entered English fully formed as a scholarly label, built to name a field rather than evolving from an older everyday sense.

It's closely related to linguistic and to linguist, both built from the same lingua-derived root meaning tongue.