乳幼児[nyuuyouji] infants
幼い[osanai] very young
幼馴染[osananajimi] childhood friend
幼魚[yougyo] fry (young fish)
幼形進化[youkeishinka] paedomorphosis

幼子[osanago] infant
幼児[youji] infant
幼児ポルノ[youjiporuno] child pornography
幼児語[youjigo] baby talk (like choo-choo for train, etc.)
幼時[youji] childhood

此の頃[konokoro] recently
一頃[hitokoro] once
何時頃[itsugoro] about when
近頃[chikagoro] lately
月頃[tsukigoro] these past months

見頃[migoro] best time to see
頃合い[koroai] suitable time
頃刻[keikoku] short period
今頃[imagoro] about this time
使い頃[tsukaigoro] handy