The lecture was
on COSMIC gas clouds.
The Big Bang Theory Season 7, Episode 17
COSMIC background radiation
from the singularity.
The Big Bang Theory Season 12, Episode 13
...he never would have found
that stupid little clump of COSMIC schmutz.
The Big Bang Theory Season 2, Episode 4
...of COSMIC radiation at sea level,
but I don't need help.
The Big Bang Theory Season 1, Episode 12