Once Ali Ibn Abi Talib Allah be pleased with him was asked regarding the meaning of Tarteel. He Allah be pleased with him replied
هُوَ تَجْوِيْدُ الْحُرُوْفِ
وَ
مَعْرِفَة الْوُقُوْفِ
Meaning; the beautification of letters(attributional consideration, articulation & intonation) and awareness of the stoppage rules.