v (intransitive) (of young animals) To emerge from an egg.
v (intransitive) (of eggs) To break open when a young animal emerges from it.
v (transitive) To incubate eggs; to cause to hatch.
v (transitive) To devise. (qualifier|hatch a plan)
n (context|poultry) A group of birds that emerged from eggs at a specified time.
n (Often as Mayfly hatch) The phenomenon, lasting 1-2 days, of large clouds of mayfly | mayflies appearing in one location (to mate, having reached maturity).
n (informal) As in the phrase "'hatched', matched, and dispatched." A birth, the birth records (in the newspaper).
v (transitive) To shade an area of a drawing or diagram with fine parallel lines, or with lines which cross each other: 'cross-hatch'.