Mishnayos Yadayim Perek 4 Mishnah 5

תרגום שכתבו עברית – The Aramaic interpretation/version that are in [the books of] Daniel and Ezra and [passages such as] (Jeremiah 10:11): “Thus you shall say to them: [Let the gods, who did not make heaven and earth, perish from the earth and from under these heavens],” if they wrote it in the Holy Tongue (i.e., Hebrew), and similarly, the words of the Prophet that are stated in the Holy Tongue that are written in Aramaic interpretation/version, do not defile the hands.

כתב עברי – the writing that comes from the other side of the river (i.e., Euphrates in Babylonia). But the Cutheans (i.e., Samaritans) write this way until today, but the Israelites would use the same script in their secular words. And on the coins that are found in our hands today that were from the time of the Kings of Israel, they are engraved with this same script. But the script that we write Scrolls with today, it is called the Assyrian script (i.e., the modern form of Hebrew type – which was brought along by the returning Babylonian captives, and made to supersede the older Syriac or Samaritan letters), and it is the script that was on the Tablets [of the Law – i.e., the Ten Commandments]. And it is called Ashuri/Assyrian, which is the most substantial of the scripts (see also Sanhedrin 22a), it is the language of (Genesis 30:13): “Women will deem me fortunate. [So she named him Asher].”