Actually,…since just adding nouns upon nouns upon nouns is possible in German, words can be long as heck. Google-searched and for a long time the longest word in the dictionary was Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz (65 letters).
“thuốc diệt cỏ không độc hại” (18 letters) translates to “non-toxic weed killer” in English.
The Finnish word “lentokonesuihkuturbiinimoottoriapumekaanikkoaliupseerioppilas” has 61 letters. It is a compound word that refers to a military rank for an apprentice aircraft jet turbine engine mechanic non-commissioned officer.