The invention concerns a device comprising: a memory containing a series of numbers and vocal prints; an acoustic transducer, for picking up a correspondent's name spoken by the user; voice recognition means, for analysing the recorded correspondent's name and transforming it into a voice print; means for selectively addressing the memory, comprising associative means, for finding in the memory a voice print information corresponding to the one supplied by the voice recognition means and, if they match, for addressing the memory on the corresponding position; and means, co-operating with the associative means, for applying to the radiotelephone circuits the addressed directory number. The voice recognition means evaluate and memorise a current sound level picked up by the transducer in the absence of a word signal; in the presence of a word signal, they subtract from the picked up signal the previously evaluated current sound level and apply on the resulting signal a DTW voice recognition algorithm with form recognition by dynamic programming adapted to the word using functions for extracting dynamic parameters, in particular a dynamic predictive algorithm with forward and/or backward and/or frequency masking.