From The Jargon File (version 4.4.7, 29 Dec 2003) :
warm boot
n.
See boot.
From The Free On-line Dictionary of Computing (30 December 2018) :
warm boot
A boot from power on, where the CPU
and peripherals are already powered up (warm).
A warm boot might be performed after a software crash or
a hardware reset.
Contrast cold boot. See also reboot.
[{Jargon File]
(1998-04-28)