From Scots cleck, from Old Norse klekja.
cleck (third-person singular simple present clecks, present participle clecking, simple past and past participle clecked)
- (chiefly Scotland) To hatch (of birds); colloquially, of people, to be born.
- 1932, Lewis Grassic Gibbon, Sunset Song, Polygon 2006 (A Scots Quair), p. 46:
- Poor he might be, but the creature wasn't yet clecked that might put on its airs with him, John Guthrie.
From Old Norse klekja.
cleck (third-person singular present clecks, present participle cleckin, past cleckit, past participle cleckit)
- to hatch, to be born