We become aware of the Celts not only by the traces they left in the landscape around us, such as hill forts and tumuli, but we also meet them in our daily language.

In spite of the time interval of about 2000 years, a few dozen words of Celtic origin have found their way into present-day German. But usually, only linguists are able to recognise them. Who would know, for example, that one of the following words ultimately originates from the Gaulish language?

• Pferd "horse" comes from Gaulish *worēdos, with prefixed para- in Latin paraverēdus „post office horse“; *worēdos also survives in Welsh gorwydd "horse" and spread as far as Persian barīd "messenger, courier".
• Karre(n) "cart" (which are not related) and English car derive from Gaulish karro- "cart, wagon". It displaced Lati­n currus and is widespread in Romance languages today.

The Celts – and the Treveri in particular – were not only famous for horse-breeding and carriage-building, where they left their marks in the vocabulary, they were also masters of ironworking and weapon technology, as a selection of examples illustrates:

• Eisen and English iron derive from Celtic *īsarno-, cf. Irish iarn, Welsh haearn [hajarn]. The word was already adopted into Germanic, cf. Gothic eisarn, Old High German îsarn. According to J.A. Harðarson (in: N. Oettinger & T. Steer [eds], Das Nomen im Indogermanischen, Wiesbaden 2014: 103–112), the Celtic and Germanic words are both inherited from Proto-Indo-European, but even then, the meaning of the Germanic word must be a loan-blend from Celtic.
• Lanze and English lance are from Celtic *lankia (via French lance and Latin lancea).

Some social and political terms date back to the time when the Celts were also politically in the lead, such as 

• Reich "kingdom, empire, rich", English rich from Celtic *rīg-, a word cognate to Latin rēx "king" and Sanskrit rāja- "king" (one need only think of maharaja "great king").
• Amt "agency, office", Old High German ampaht, English embassy, ambassador etc., from Gaulish ambactos "servant liegeman", literally "he who is carried about, who is at someone's disposal"; in Welsh we find amaeth "farm worker".
• Vasall and English vassal from Gaulish *wassalo-, *wossalo- "subordinate"; this word was also mediated through Latin, where it had become vassallus.

On the rivers Moselle and lower Saar, a descendant of late spoken Latin survived from the fifth until the eleventh century, the so-called Moselle-Romanesque. In this language, some more Gaulish words have been preserved: 

• Bäschoff "back carrier of the wine-growers", like English basket, comes from Gaulish bascauda "wicker basket", via Anglo-French bascat; it was said to be Celtic by the Roman poet Martial.
• Karch "wheelbarrow" from Gaulish carruca "cart, (wheel)plough", like French charrue "plough".
• Lei "slate, rock" derives from Gaulish lika, likka "flat stone, slab", cf. Welsh llech.
• Olk, Ollek "wasteland, fallow" is from Gaulish olca "farmland", French ouche.

Finally, some words from the Celtic languages of the British Isles reached German via English as e.g.

• Clan from Irish clann [klann] "children".
• Slogan from Gaelic sluagh-ghairm [slua-charim] "battle cry" (this meaning was still preserved in England in the 16th century).
• Whisk(e)y from Gaelic uisge beatha [uschge bjaha] "water of life" (coined after Latin aqua vitae).