Plus fort que le mot le plus long du monde...

...l'acronyme le plus long du monde

The world's longest initialism, according to the Guinness Book of World Records is NIIOMTPLABOPARMBETZHELBETRABSBOMONIMONKONOTDTEKHSTROMONT (Нииомтплабопармбетзелбетрабсбомонимонконотдтехстромонт).

The 56-letter initialism (54 in Cyrillic) is from the Concise Dictionary of Soviet Terminology and means "The laboratory for shuttering, reinforcement, concrete and ferroconcrete operations for composite-monolithic and monolithic constructions of the Department of the Technology of Building-assembly operations of the Scientific Research Institute of the Organization for building mechanization and technical aid of the Academy of Building and Architecture of the USSR."