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

若し[moshi] if
若しかしたら[moshikashitara] perhaps
若しかして[moshikashite] perhaps
若しかすると[moshikasuruto] perhaps
若い[wakai] young

若さ[wakasa] youth
若しくは[moshikuha] or
若干[jakkan] some
若死に[wakajini] premature death
若者[wakamono] young man