御爺さん[ojiisan] grandfather
老爺[shinpu] one's father
狸爺[tanukijijii] cunning old man
好々爺[koukouya] good-natured old man
爺が背[hizaragai] chiton (any marine mollusk of the class Polyplacophora)

エロ爺[erojijii] dirty old man
糞爺[kusojijii] old man
爺さん[jiisan] grandfather (may be used after name as honorific)
洞爺湖サミット[touyakosamitto] G8 Hokkaido Toyako Summit

老麺[raamen] ramen (Chinese-style noodles)
家老[karou] chief retainer
棄老[kirou] old person thrown away in the mountains
敬老[keirou] respect for the aged
敬老の日[keirounohi] Respect-for-the-Aged Day Holiday (third Monday in September)

元老[genrou] elder statesman
元老院[genrouin] (Roman) senate
故老[korou] old people
車海老[kurumaebi] kuruma prawn (Marsupenaeus japonicus)
寿老人[juroujin] god of longevity