A syllable applied in solmization to the second tone of the diatonic scale of C; in the American system, to the second tone of any diatonic scale.
Webster 1828 Edition
Re
RE
, a prefix or inseparable particle in the composition of words, denotes return, repetition, iteration. It is contracted from red, which the Latins retained in words beginning with a vowel, as in redamo, redeo, redintegro. In a few English words, all or most of which, I believe, we receive from the French, it has lost its appropriate signification, as in rejoice, recommend, receive.