1.
without doubt (used for emphasis). Inner side of a person, object or thing
certainly
surely
for sure unquestionably
without/beyond doubt
without/beyond question beyond any doubt
undoubtedly
indubitably assuredly
positively
absolutely in a definite manner; clearly.
inner side of something.
interior
inner part
2.
the inner part; the interior.
situated in, or derived from, the inside.
inner
interior
internal
inmost
innermost
Setting: (nightlife in a bar)
Guy walks up to a girl in a bar....
Guy: "Do you know when I am indefinitely?"
Girl:"Indefinitly?"
Guy:"When my balls are smackin you, in the ass! That's when I know, I am IN DEFINITLY"!
"Sir, we found something that is going to spread and become infinite."
"Well do we know how long this is going to occur?"
"No sir, it is indefinitely infinite."