Technical term in genetics for a cell or organism having a single set of unpaired chromosomes.
半数体の細胞は、染色体を一組だけ持つ。
A haploid cell has only one set of chromosomes.
酵母の半数体株を用いて実験を
We conducted an experiment using a haploid strain of yeast.
Compound of 半数 (half number) + 体 (body, entity), referring to an organism or cell with half the usual chromosome number.