| Subject | English | Portuguese |
| commun. | double tone multiple frequency | multifrequência de duas tonalidades |
| comp., MS, Braz. | dual-tone multiple-frequency | multifrequência de tom dual (The signaling system used in telephones with touchtone keypads, in which each digit is associated with two specific frequencies) |
| comp., MS | dual-tone multiple-frequency The signaling system used in telephones with touchtone keypads, in which each digit is associated with two specific frequencies | DTMF (Dual Tone Multiple-Frequency) |
| el. | multiple frequency | de frequência múltipla |
| commun. | multiple frequency environment,to distribute in a- | ambiente multifrequência, distribuir num- |