G3727 — horkos
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
horkos — pronounced hor'-kos
from herkos (a fence; perhaps akin to 3725); a limit, i.e. (sacred) restraint (specially, an oath):--oath. see GREEK for 3725
10 occurrences in the KJV.
Matthew 5:33
Again, ye have heard that it hath been said by them of old time, Thou shalt not forswear thyself, but shalt perform unto the Lord thine oaths:
Matthew 14:7
Whereupon he promised with an oath to give her whatsoever she would ask.
Matthew 14:9
And the king was sorry: nevertheless for the oath’s sake, and them which sat with him at meat, he commanded it to be given her.
Matthew 26:72
And again he denied with an oath, I do not know the man.
Mark 6:26
And the king was exceeding sorry; yet for his oath’s sake, and for their sakes which sat with him, he would not reject her.
Luke 1:73
The oath which he sware to our father Abraham,
Acts 2:30
Therefore being a prophet, and knowing that God had sworn with an oath to him, that of the fruit of his loins, according to the flesh, he would raise up Christ to sit on his throne;
Hebrews 6:16
For men verily swear by the greater: and an oath for confirmation is to them an end of all strife.
Hebrews 6:17
Wherein God, willing more abundantly to shew unto the heirs of promise the immutability of his counsel, confirmed it by an oath:
James 5:12
But above all things, my brethren, swear not, neither by heaven, neither by the earth, neither by any other oath: but let your yea be yea; and your nay, nay; lest ye fall into condemnation.