Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
quran:89:3

And ˹by˺ the even ˹number˺ and the odd  

and ˹by˺ the even, the pair, and the odd (read watr or witr, two ˹alternative˺ forms), the single,
القرآن:٨٩:٣

وَالشَّفْعِ وَالْوَتْرِ  

{والشفع} الزوج {والوتر} بفتح الواو وكسرها لغتان: الفرد.