What is Aforethought?

Legal Definition
Crim. law. Premeditated, prepense; the length of time during which the accused has entertained the thought of committing the offence is not very material, provided he has in fact entertained such thought; he is thereby rendered criminal in a greater degree than if he had committed the offence without. premeditation. Vide Malice; aforethought; Premeditation 2 Chit. Cr. 785; 4 Bl. Com. 199; Fost. 132, 291, 292; Cro. Car. 131; Palm. 545; W. Jones, 198; 4 Dall. R. 146; 1 P. A. Bro. App. xviii.; Addis. R. 148; 1 Ashm. R. 289.
-- Bouviers Law Dictionary
Legal Definition
In criminal law. Delibsrate; planned; premeditated; prepense. State v. Peo, 9 Houst (Del.) 488, 33 Atl. 257; Edwards v. State, 25 Ark. 444; People v. Ah Choy, 1 Idaho, 317; State v. Fiske, 63 Co.nn. 388, 28 Atl. 572.
-- Black's Law Dictionary
Legal Definition
Premeditated.
-- Ballentine's Law Dictionary