1) Certain ions 2) Ion with a positive charge 3) Positive particles 1) Ions 
Ion with a positive charge.
An ion consists of one or more atoms and carries a unit charge of electricity. Those that are positively electrified (hydrogen and the metals) are called cations (cf. anion).
Postively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis. ... (12 Dec 1998) ... 
(kat;i-onz) Positively charged ions, such as sodium, potassium, calcium, and magnesium.
Ion with a positive charge.
Ion with a positive charge. Metals typically form cations. See also: Anion.