夏至[geshi] summer solstice
夏至線[geshisen] Tropic of Cancer
夏至点[geshiten] summer solstitial point
至って[itatte] very much
至らない[itaranai] imperfect

至る[itaru] to arrive at (e.g. a decision)
至る処[itarutokoro] everywhere
至れりつくせり[itareritsukuseri] very polite
至急[shikyuu] urgent
至急便[shikyuubin] express mail

適わない[kanawanai] no match for
快適[kaiteki] pleasant
快適さ[kaitekisa] amenity
適う[kanau] to come true (wish)
適える[kanaeru] to grant (request, wish)

好適[kouteki] ideal
最適[saiteki] optimum
最適化[saitekika] optimization
素適[suteki] lovely
適確[tekkaku] precise