Syrian language (tongue) Syriac

Boyd’s Bible Dictionary:

The ancient language of Syria, an Aramean dialect
In Daniel 2:4, the word “Syriac” should read “Aramaic,” the court language of Babylon at the time.

Concise Bible Dictionary:

The language that was spoken in Syria was substantially the same as Chaldee. The Hebrew word is aramith. See ARAMAIC (2 Kings 18:26; Ezra 4:7; Isa. 36:11; Dan. 2:4).

Strong’s Dictionary of Hebrew Words:

Transliteration:
’Aramiyth
Phonic:
ar-aw-meeth’
Meaning:
feminine of 761; (only adverbial)in Aramean
KJV Usage:
in the Syrian language (tongue), in Syriac

Potts’ Bible Proper Names:

Ancient language of Syria, an Aramean dialect; Aramaic, Dan. 2:4.