M phase occurring as part of the meiotic cell cycle. M phase is the part of the cell cycle during which nuclear division takes place. A meiotic cell cycle is one in which canonically a cell replicates to produce four offspring with half the chromosomal content of the progenitor cell.
Note that this term should not be used for direct annotation. If you are trying to make an annotation to x phase, it is likely that the correct process is 'regulation of x/y phase transition'.