The late stage of prophase I of meiosis I in which homologous chromosome pairs begin to separate and move away from one another except at chiasmata.
During the first prophase of meiosis I, there are five sub-stages:
leptotene, zygotene, pachytene, diplotene and diakinesis.
Word origin: from Greek words meaning "two threads"
See also: meiosis, prophase I, diplonema