What are basal theropods?

Some articles on basal theropods, basal, theropod, basal theropod:

Herrerasauridae - Classification
... They are possibly basal theropods or basal saurischians but may in fact predate the saurischian-ornithischian split. 2009, have found Herrerasaurus and its relatives in Herrerasauridae to be very basal theropods, while others (such as Ezcurra 2010) have found them to be basal to the clade ... Other possible basal theropods, Alwalkeria from the Late Triassic Maleri Formation of India, and Teyuwasu, known from very fragmentary remains from the Late ...
Herrerasaurus - Classification
... Herrerasaurus is a primitive saurischian, but not a theropod ... This analysis indicated that Herrerasaurus was a basal theropod ... Most 21st-century analyses have found them to be basal theropods, though they may in fact represent basal saurischians or even be non-dinosaurian, predating the saurischian-orn ...