Longman Dictionary of Contemporary English - dawn

~1 n 1 the time at the beginning of the day when light first appears  (We talked almost until dawn. | at dawn)  (The first boats set off at dawn. | dawn breaks (=the first light of the day appears))  (When dawn broke we were still 50 miles from Calcutta. | at the crack of dawn (=very early in the morning))  (I was up at the crack of dawn to get the plane.)  (- compare dusk) 2 the dawn of civilization/time etc the time when something began or first appeared  (People have been falling in love since the dawn of time.) 3 a false dawn something that seems positive or hopeful but really is not  (another false dawn on the road to recovery) ~2 v 1 if day or morning dawns, it begins  (The morning dawned fresh and clear after the storm.) 2 literary if a period of time or situation dawns, it begins  (The age of Darwin had dawned.) 3 formal if a feeling or idea dawns, you think of it for the first time dawn on sb phr v T not in passive if a fact dawns on you, you realise it for the first time  (Then the ghastly truth dawned on me. | it dawns on sb that)  (It dawned on me that Joanna had been right all along.)