Read the passage:
'Nollywood, the colloquial moniker for the Nigerian film industry, emerged in the early 1990s as a grassroots cultural phenomenon propelled by straight-to-video releases such as Kenneth Nnebue's Living in Bondage (1992). Bypassing traditional celluloid film infrastructure, resourceful Nigerian directors harnessed affordable VHS camcorders and rapid digital editing suites to produce compelling narratives reflecting urban life, moral dilemmas, and spiritual themes. Today, Nollywood stands as one of the world's largest film producers by volume, transitioning from informal street markets in Idumota to international cinema chains and digital streaming platforms.'

What does the word 'colloquial' mean in the opening sentence?