粗大 is read as そだい (sodai) and means coarse.
そだい
sodai
そだいうんどう
gross motor skill
そだいごみ
useless man about the house
そまつ
crude
あらい
coarse
あらすじ
outline
そしな
gift given out by companies to customers as a token of gratitude
そあく
そや
rustic
そぼう
rough (behaviour, temperament, etc.)
そこう
crude steel
あらけずり
rough-hewn
そざつ