Viviparous: Offspring developing while still attached to the parent plant, as with seeds germinating in fruits still attached to the parent plant (e.g., mangroves, Avicennia, Rhizophora), or buds that form plantlets while still attached to the parent plant (often on leaves, e.g., waterlilies, Nymphaea)*
This Kalanchoe is producing plantlets all along the margins of its leaves. The plantlets are complete with roots and leaves so they’re ready to grow as soon as they drop to the ground.
*Pell, S.K., Angell, B. (2016). A botanist’s vocabulary: 1300 terms explained and illustrated. Portland: Timber Press.