What is "nuncupative testament"

Nuncupative \Nun*cu"pa*tive\, a. [L. nuncupativus nominal: cf. F. nuncupatif.]

1. Publicly or solemnly declaratory. [Obs.]

2. Nominal; existing only in name. [Obs.]

3. Oral; not written.

   Nuncupative will or Nuncupative testament, a will or testament made by word of mouth only, before witnesses, as by a soldier or seaman, and depending on oral testimony for proof.
   --Blackstone.