noun.
Any of the four haploid cells that are formed by meiosis from a spermatocyte and that develop into spermatozoa without further division.
The Century Dictionary and Cyclopedia
noun.
One of the two cells which arise by division of a secondary spermatocyte and give rise by transformation to a spermatozoön. In oögenesis the spermatid is represented by the oötid.