What respectively are zygotic meiosis, gametic meiosis and sporic meiosis?

Zygotic meiosis is the one that happens in the haplontic haplobiontic life cycle. Gametes from adult haploid individuals unite forming the diploid zygote. The zygote undergoes meiosis and generates four haploid cells that by mitosis develop into adult individuals. Thus in the zygotic meiosis the cell that undergoes meiosis is the zygote and the gametes are produced by mitosis.

Sporic meiosis occurs in metagenesis (alternation of generations, or diplobiontic life cycle). In this life cycle cells from the diploid individual (called sporophyte) undergo meiosis producing haploid spores that do not unite with others but instead develop by mitosis into haploid individuals (known as gametophytes). In this life cycle the gametes are made by mitosis from cells of the gametophyte.