(music) The principal part of a duet.

(colloquial) Best; first-class.

plural of primo

The male lead in an opera.

The state of being the firstborn of the children of the same parents. / The principle that the eldest child has an exclusive right of inheritance.

first, earliest or original / (biology) characteristic of the earliest stage of the development of an organism, or relating to a primordium / primeval

A first principle or element.

(informal, evolutionary theory) The state of the Earth's oceans at a very early time in the planet's history, during the early development of multicellular organisms.

(anatomy) An aggregation of cells that is the first stage in the development of an organ.

plural of primogenitor