On God

Meaning. I swear; being completely honest

See it in a sentence

On God, I didn't take your phone.

How each generation says it

The closest equivalent for this idea in every generation.

Admirably true to oneself, or agreeing with an opinion regardless of others.

Abbreviation meaning nonsense or a lie.

A lie, nonsense, or exaggeration.

A lie or exaggeration; to lie.