Ma'anar ƙamus na kalmar "megaspore" wani ɗan ƙaramin haploid spore ne wanda wasu tsire-tsire ke samarwa, musamman iri da wasu ferns, kuma yana haifar da gametophyte na mace. Megaspores yawanci suna samuwa a cikin ovules na shuka kuma suna da mahimmanci don haifuwa ta jima'i. Suna haɓaka zuwa gametophytes na mata, wanda ke ɗauke da ƙwayoyin ƙwai waɗanda maza gametophytes (pollen) suka hadu don samar da iri.