Denshi Jisho — Online Japanese dictionary

亘古 こうこ for ever; from ancient times
Noun, Archaism 
亘る わたる 1: to cross over; to go across;
2: to extend; to cover; to range; to span
Godan verb with ru ending, Intransitive verb 
求める もとめる 1: to want; to wish for;
2: to request; to demand;
3: to seek; to search for; to pursue (pleasure); to hunt (a job);
4: (Polite language) to purchase; to buy
Common word, Ichidan verb, Transitive verb 

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