An information processing device including an electronic control unit is provided. The electronic control unit is configured: to acquire speech data which is uttered by a user; to acquire context in associated with a situation of the user; to convert the speech data into text data; to select a dictionary which is referred to for determining a meaning of a word included in the text data based on the context information when the speech data has been acquired; to give the meaning of the word determined with reference to the selected dictionary to the text data; and to provide a service based on the text data to which the meaning of the word is given.