異姓[isei] different surname
下姓[geshou] person of humble birth
改姓[kaisei] changing one's family name
旧姓[kyuusei] one's former (maiden) name
姓氏[seishi] full name

姓名[seimei] full name
種姓[sujou] birth
俗姓[zokushou] secular surname (of a priest)
他姓[tasei] another surname

偏芯[henshin] eccentricity (in mechanics, electronics, etc.)
燈芯[toushin] (lamp) wick
帯芯[obishin] thick obi sash
摘芯[tekishin] thinning (buds and branches)
芯地[shinji] padding

替え芯[kaeshin] spare lead
鉛筆の芯[enpitsunoshin] lead of a pencil
硬の芯[kounoshin] hard pencil lead
林檎の芯[ringonoshin] core of an apple