sub·crit·i·cal adjective \-ˈkri-ti-kəl\
: less or lower than critical in respect to a specified factor
a : of insufficient size to sustain a chain reaction <a subcritical mass of fissionable material>
b : designed for use with fissionable material of subcritical mass <a subcritical reactor>
First Known Use of SUBCRITICAL
Seen & Heard
What made you want to look up subcritical? Please tell us where you read or heard it (including the quote, if possible).