The Jargon File (version 4.4.7, 29 Dec 2003):

bathtub curve
 n.

    Common term for the curve (resembling an end-to-end section of one of those
    claw-footed antique bathtubs) that describes the expected failure rate of
    electronics with time: initially high, dropping to near 0 for most of the
    system's lifetime, then rising again as it ?tires out?. See also burn-in
    period, infant mortality.


The Free On-line Dictionary of Computing (30 December 2018):

bathtub curve

   Common term for the curve (resembling an end-to-end section of
   one of those claw-footed antique bathtubs) that describes the
   expected failure rate of electronics with time: initially
   high, dropping to near 0 for most of the system's lifetime,
   then rising again as it "tires out".  See also burn-in
   period, infant mortality.

   [Jargon File]