希望【きぼう】
hope, wish, aspiration, (bright) prospects, expectation
希薄【きはく】
thin (air), weak (liquid), dilute, sparse (population), rarefied, lacking (enthusiasm, consideration, substance, etc.), insubstantial, deficient, tenuous (link)
希少【きしょう】
scarce, rare
古希【こき】
70th birthday, ancient Greek (language)
希代【きたい】
uncommon, rare, extraordinary, matchless
希求【ききゅう】
longing, great desire, aspiration
希望的【きぼうてき】
wishful