Definition of chloroplast in US English:

chloroplast

noun

Botany
  • (in green plant cells) a plastid that contains chlorophyll and in which photosynthesis takes place.

    • ‘Ripening of tomato fruit involves the differentiation of chloroplasts in young green fruit into chromoplasts in mature ripe red fruit.’
    • ‘As Zeiger et al. have recently emphasized, guard cell chloroplasts show remarkable functional plasticity.’
    • ‘Even in the late stages of leaf senescence, the chloroplasts of guard cells remain green and functional.’
    • ‘Fluorescence of guard cell chloroplasts was imaged when plants were at approximately the six-leaf stage.’
    • ‘The outer layer of the abaxial epidermis contains sunken stomata with strongly fluorescing chloroplasts in the guard cells.’

Origin

Late 19th century: coined in German from Greek khlōros ‘green’ + plastos ‘formed’.

Pronunciation

chloroplast

/ˈklôrəˌplast/