The low-growing bush basil (Ocimum minimum) is a separate species, but it is probably a variant of sweet basil. Much of the herb grown today is a hybrid, a cross between Ocimum basilicum andOcimum americanum. There are many cultivars of basil that have their own denomination.
Tukmaria and sabza are another name for basil seeds. Tukmaria has a very mild flavour (rather like poppy seeds) and is generally used in light desserts thanks to its gelatinous properties when it's soaked and swells in water