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

誠に[makotoni] indeed
誠意[seii] sincerity
誠実[seijitsu] sincere
誠心誠意[seishinseii] in all sincerity
丹誠[tansei] working earnestly

忠誠[chuusei] loyalty
不誠意[fuseii] insincerity
不誠実[fuseijitsu] insincerity
至誠[shisei] sincerity