The word used in Luke 1:36 is a koine Greek word sugennes. It means that Mary and Elizabeth were somehow related; that relationship could have been by blood or by ethnicity or whatever. It indicates kinship of unspecified type. The idea that Mary was a first cousin to Elizabeth is a 3rd century, extra-biblical fabircation by Hyppolitus.
I think our problem is not that we do not know Greek, but that that we do not know English as well as the KJB translators knew English.
The word “cousin” can in fact be used to mean a more general relationship. According to the Oxford International Dictionary before me, it can mean:
*Any collateral relative;
*(One’s next of kin;
*A title used formally of one monarch to another monarch;
*A person or thing having affinity of nature to another;
*A person of kindred race or nation;
*A prostitute;
*A dolt;
*A cousin once, twice, etc. removed (a) the child, grandchild, etc. of a cousin; (b) the cousin of a parent, grandparent, etc. . . .
*Kindred; related
*And more.
* * * * * * *
I think we need to study more English than Greek. The word “cousin” means, precisely as the koine Greek word, suggennes.
Our ignorance of the vastness of English is not a basis for criticism of the KJB translators.
They chose a great word, “cousin.”