period when a system is unavailable

DOWNTIME
List of words for the clue period when a system is unavailable from the crossword:
ETD TURN ERA EON LENT ETA AGE ACTI DAY ETE ACTII EVE EEN ENERO TEN AGES DST ANO APRIL
WordClue
AGEera, period
ERAperiod, epoch
NAPshort period of sleep
LULLperiod of rest
SALLYWhen Harry Met ... (film)
FREEZEperiod of intensely cold weather
SEASONinterval, period
INFANCYperiod of childhood
PERMIANgeologic period
CAMBRIANgeologic period
DEVONIANgeologic period
INTERVALperiod, pause
JURASSICgeologic period
SILURIANgeologic period
TIMESPANperiod
TRIASSICgeologic period
PALEOGENEgeologic period
CRETACEOUSgeologic period
ORDOVICIANgeologic period
CARBONIFEROUSgeologic period
INTERVALperiod, pause
VISIONperipheral or stereoscopic