There are two (different) Greek root words here.
The one in the Bible (at least 115 times) is (so, this is the meaning of church in the Bible)
Ecclesia – The Greek word “ecclesia” is correctly defined as: “The called-out (ones)” [ECC = out; KALEO = call]. Thus, you can see how this word was used to indicate a civil body of select (called, elected) people.
Quoting from the Oxford Universal English Dictionary on the word “ecclesia”:
Ecclesia [mediaeval Latin, and Greek – from : SUMMONED] -A regularly convoked assembly, especially the general assembly of Athenians. Later, the regular word for church. assembly
When the greeks (romans?) wanted to make an announcement, they would call people out of their homes to the street. ecclesea.
The English word ‘church’ is a different Greek word.
“Church” comes from the Old English and German word pronounced “kirche.” In Scotland, it was “kirk.”
In the earlier Greek It was pronounced “ku-ri-a-kos” or “ku-ri-a-kon.” As you can see, this word doesn’t even resemble the Greek word “ecclesia” whose place it has usurped. The meaning of “Ku-ri-a-kos” is understood by its root: “Ku- ri-os,” which means “lord.” Thus, “kuriakos” (i.e., “church”) means “pertaining to the lord.” It refers to something that pertains to, or belongs to, a lord. The Greek “kuriakos” eventually came to be used in Old English form as “cirice” (Kee-ree-ke), then “churche” (kerke), and eventually “church” in its traditional pronunciation. A church, then, is correctly something that “pertains to, or belongs to, a lord.” Lord’s house.
An interesting quote from the 1915 “Gospel Advocate” (Pg 589) says:
“The word ‘Church’ is really not a translation of any word that was used by either Christ or His Apostles, but is the Anglican form of a different word which Roman Catholicism substituted in place of the word used by Christ and His Apostles… It is in our english scriptures by order of King James, who instructed his translators of 1611 not to translate the word “Ecclesia” by either ‘Congregation’ or ‘Assembly’ but to use the word ‘Church’ instead of a translation.”
Etymology of the word “Church”
http://www.aggressivechristianity.net/articles/ecclesia.htm (has a negative tone)