Answer: sub

AnswerCrossword Clue
SUBStand in
SUBU-boat, e.g.
SUBDeli choice
SUBHefty sandwich
SUBTorpedo, or its launcher
SUBOcean traveler
SUBRed October, for one
SUBSizable sandwich
SUBPinch hitter
SUBSonar user
SUBThe Nautilus, for one
SUBBenchwarmer
SUBTemp
SUBLong lunch, for short
SUBLarge sandwich, for short
SUBCome off the bench (for)
SUBLead-in for zero or prime
SUBDiving craft
SUBOne may be needed after a sports injury
SUBUndersea prowler
subto act as a substitute
SUBPlayer off the pine
SUBTemp. teacher
SUBDeli order, sometimes
SUBHero
SUBBench-warmer
SUBGrinder's kin
SUBStand-in
SUB"Nautilus," for one
SUBSecond-stringer
SUBLong lunch?
SUBDeli offering
SUBLunch on a roll
SUBThe USS Jimmy Carter, e.g.
SUBTeacher for a day
SUBTemporary teacher
SUBPlayer filler in
SUBLong sandwich
SUBNautilus, e.g.
SUBOne may be needed after an injury