hold fast, keep(- er), (pre-, re-)serve, watch
Strong’s Dictionary of Greek Words:
Meaning:
from τερός (a watch; perhaps akin to 2334); to guard (from loss or injury, properly, by keeping the eye upon; and thus differing from 5442, which is properly to prevent escaping; and from 2892, which implies a fortress or full military lines of apparatus), i.e. to note (a prophecy; figuratively, to fulfil a command); by implication, to detain (in custody; figuratively, to maintain); by extension, to withhold (for personal ends; figuratively, to keep unmarried); by extension, to withhold (for personal ends; figuratively, to keep unmarried)
KJV Usage:
hold fast, keep(- er), (pre-, re-)serve, watch