Monoembryonic variety of lemon is

The monoembryonic variety of lemon is Meyer. Monoembryony is the emergence of one and only one seedling from a seed.
Meyer lemon is a hybrid citrus fruit native to China. It is a cross between a citron and a mandarin/pomelo hybrid.
The fruit is rounder than a true lemon, deep yellow with a slight orange tint when ripe and has a sweeter, less acidic flavour. The lemons contain a highly acidic pH of between 2 - 3. This acidity level allows for these lemons to be used as antibacterial and antiseptic cleaners.