= Pseudobulge
A <pseudobulge> is a central stellar concentration in a disk <galaxy> whose structure and dynamics indicate growth through internal disk evolution rather than only rapid merger-driven assembly. A central brightness excess alone does not establish this origin.
Disk-like flattening, appreciable ordered rotation, nuclear <spiral arms>, <galactic bars> and ongoing <star formation> provide complementary diagnostics. A bar can <torque> <gas> and move it inward, feeding central <star formation> over a long timescale. Individual diagnostics are imperfect, so classifications combine imaging and kinematics instead of equating every low-index brightness profile with a unique history.<Secular Evolution and the Formation of Pseudobulges in Disk Galaxies by John Kormendy and Robert C. Kennicutt Jr.>[Abstract, disk-like diagnostics and bar-driven gas redistribution]{ref}
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