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

嘘っ八百[usoppappyaku] full of lies
嘘八百[usohappyaku] full of lies
何百[nanbyaku] hundreds
五十歩百歩[gojuppohyappo] six of one and a half dozen of the other
三百[sanbyaku] 300

三百諸侯[sanbyakushokou] all the daimyos
三百代言[sanbyakudaigen] pettifogging lawyer
数百[suuhyaku] several hundreds
生誕百年[seitanhyakunen] 100th birthday anniversary
二百十日[nihyakutooka] 210th day (from the first day of spring according to the lunar calendar)