Answer: lagged

AnswerCrossword Clue
LAGGEDFell behind
LAGGEDDidn't keep up
LAGGEDWaned
LAGGEDBrought up the rear
LAGGEDFell back
LAGGEDFell behind.
LAGGEDDawdled.
laggedinstance of lagging
laggedto fall behind; move slowly or belatedly
laggedLAG, to fall behind
laggedinterval