One of the more common etymologies given for
Samantha in 20th century baby name books was "Aramaic: Listener." The earliest example of this I can find on short notice is from "Name Your Baby" by Lareina Rule, 1973 edition, original publication 1963. Once something like this is in print it gets copied in other baby name books -- for example "A Treasury of Baby Names" by
Alan Benjamin (1983) and "Parents' Book of Baby Names" by
Martin Kelly (1985) give the same derivation. I wish I knew who first came up with this idea.
An online English to Aramaic dictionary I have found yields "שָׁמְעָא" (
Sham'a) as Aramaic for "listener." It's probable someone looking for an origin for
Samantha in a Semitic language (so it could be related to
Samuel) found that and wrongly assumed it was the origin of
Samantha. Given Retrospectre's research, an alternation of the literary name Semanthe under the influence of
Samuel and -antha is more plausible.