Definition. 1  A lumpectomy is a type of surgery used to treat breast cancer. It is considered breast-conserving surgery because in a lumpectomy, only the malignant tumor and a surrounding margin of normal breast tissue are removed. 2  Lumpectomy is a surgical treatment for newly diagnosed breast cancer. It is estimated that at least 50% of women with breast cancer are good candidates for this procedure. The location, size, and type of tumor are of primary importance when considering breast cancer surgery options.
A triadic melody is a melody made up of triads. Triads are chordsconsisting of three tones. The triad consists of the root tone, amajor or minor.
Webster Dictionary(0.00 / 0 votes)Rate this definition: 1  Triad(noun) a union of three; three objects treated as one; a ternary; a trinity; as, a triad of deities. 2  Triad(noun) a chord of three notes. 3  Triad(noun) the common chord, consisting of a tone with its third and fifth, with or without the octave.