1) Human action 2) Human activity 3) The act of making lawful 1) Legalisation 2) Legalization 
Legitimation or legitimization is the act of providing legitimacy. Legitimation in the social sciences refers to the process whereby an act, process, or ideology becomes legitimate by its attachment to norms and values within a given society. It is the process of making something acceptable and normative to a group or audience. Legitimate power is...
• (n.) Lawful birth. • (n.) The act of making legitimate.
(from the article `illegitimacy`) An illegitimate child`s status may be changed by a legal action called legitimation, granting him all the rights of legitimate children—except that ...
Le·git`i·ma'tion (-mā'shŭn) noun [ Confer French légitimation .] 1. The act of making legitimate. « The coining or legitimation of money.» East. 2. Lawful birth. [ R.] Shak. 
[n] - the act of rendering a person legitimate
an action brought to prove paternity of a child.