I cannot find a dictionary entry for the word "concantate ". Is it a
specific computer term? What is it's etymology? Thanks in advance for
yoru reply.

tonyso --

For several reasons, I believe that the term you are looking for is
"concatenate."
 
First, after a thorough search, I have been unable to find a
definition of "concantate."

Second, you identify the word "concantate" as a "computer term." 
"Concatenate," which is very similar to "concantate" in spelling and
pronounciation, is a common computer science term.  Its dictionary
definition is "[t]o arrange (strings of characters) into a chained
list."  Its etymology is, "Late Latin concatenare, concatenat-:com-, +
catenare, to bind (from Latin catena, chain)." The American Heritage
Dictionary of the English Language, Fourth Edition, Houghton Mifflin
Company (2000).

Finally, A Google search for the term "concantate" turns up only five
references to the word, at least four of which appear in context to be
misspellings of "concatenate." (In contrast, a search for the term
"concatenate" turns up 122,000 results.)

The complete search results using "concantate" are at this linked
page:
://www.google.com/search?sourceid=navclient&q=concantate

The following link to a more detailed definition of "concatenation" as
used in computer science may be helpful to you.
Whatis,com Target Search
http://whatis.techtarget.com/definition/0,,sid9_gci214438,00.html

I hope this is the information you are looking for.  If it is not,
please request a clarification of my answer, and I will keep trying.

markj-ga

Excellent and thorough. Thanks!