τηρέω
tēréō
tay-reh'-o
from a Greek word not found in the New Testament (a watch; perhaps akin to θεωρέω); to guard (from loss or injury, properly, by keeping the eye upon; and thus differing from φυλάσσω, which is properly to prevent escaping; and from κουστωδία, 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 translates as: hold fast, keep( er), (pre, re)serve, watch