||God said to Moses, 'Tell Aaron to take his staff and extend his hand over the waters of Egypt - over their rivers, their canals, their reservoirs, and every place where water is kept - and [the water] shall turn into blood. There will be blood throughout all Egypt, even in wooden [barrels] and stone [jars].'
Vayomer Adonay el-Moshe emor el-Aharon kach matecha unteh-yadecha al-meymey Mitsrayim al-naharotam al-ye'oreyhem ve'al-agmeyhem ve'al kol-mikveh meymeyhem veyihyu dam vehayah dam bechol-erets Mitsrayim uva'etsim uva'avanim.
(Rashi; Targum). Y'orim in Hebrew (Cf. Daniel 12:5). Or, 'streams.' The word is usually assumed to denote irrigation canals (Radak, Sherashim; Sekhel Tov), because they flow from the Nile, which is known as the Y'or (Ibn Janach). The term usually refers to Egyptian canals (2 Kings 19:24, Isaiah 7:18, 19:6, 37:25). The word y'or is thought to be related to the ancient Egyptian iaur or aur, a canal, stream, or arm of the Nile. In Coptic, the word is eiero or eioor.
Agam-im in Hebrew. It is thus translated in Old French as astonc (Rashi), and in Spanish as estanque (Radak, Sherashim). It can also denote a lake or pool (palude in Spanish; Radak, Sherashim). Others write that this is any gathering of rain water (Ibn Ezra). The word may therefore be related to the Egyptian, since ag is a flood, and agem or agep is rain.
|where water is kept|
Literally, 'gatherings of water.' These denote cisterns and wells (Ibn Ezra).
(Targum; Rashi; Ibn Ezra). In ancient Semitic texts, a similar expression means 'woods and fields.' It is questionable whether or not this last sentence is part of what Moses was to tell Aaron.