Strong's G2583 — κανών (noun)
kanon (kan-own') n.
1. a rule ("canon")
2. (figuratively) a standard (of faith and practice)
3. (by implication) a boundary
4. (figuratively) a sphere (of activity)
[from kane "a straight reed, i.e. rod"]
KJV: line, rule 
Occurrences: 4