Difference between Unbelievable and Terrific

UNBELIEVABLE vs TERRIFIC: ADJECTIVE

Used especially as intensifiers
Extraordinarily good or great
Causing terror; fitted to excite great fear or dread; dreadful: as, a terrific storm.

Dumfounding, Marvellous, Tall, Unlikely, Undreamed, Unconvincing, Unimagined, Undreamt, Dumbfounding, Implausible, Improbable, Fabulous, Marvelous, Astounding, Incredible

Phenomenal, Excellent, Superb, Great, Rattling, Alarming, Howling, Intense, Terrifying, Wondrous, Extraordinary, Tremendous, Marvelous, Wonderful, Fantastic

Dumfounding, Marvellous, Tall, Unlikely, Undreamed, Unconvincing, Unimagined, Undreamt, Dumbfounding, Implausible, Improbable, Fabulous, Marvelous, Astounding, Incredible

Phenomenal, Excellent, Superb, Great, Rattling, Alarming, Howling, Intense, Terrifying, Wondrous, Extraordinary, Tremendous, Marvelous, Wonderful, Fantastic

The facts in this case are almost unbelievable.
Completely unbelievable premise, not in a good way.
It means that she got her unbelievable orgasm.
Unbelievable that any service cannot cope with GRs.
Unbelievable answer and zero empathy tonsolve the situation.
And we had an unbelievable amount of leftovers.
Today it all seems rather ridiculous and unbelievable.
Your satisfaction is our top priority and we want you to feel that you got an unbelievable deal at an unbelievable price.
And we would find like unbelievable points, unbelievable points.
Of all the unbelievable suppositions, this seems to be the most unbelievable.

Nigeria is also home to some terrific food.
This is a terrific budget electric fence system.
Having the bikes as an option was terrific.
We had a terrific time on the Valor.
Our originations team is doing a terrific job.
California, this New York Life policy is terrific.
Terrific purchase for a mattress without nasty chemicals.
Our experience with Park N Go was terrific!
It was a terrific finals by everybody really.
He pulled together a terrific crew on short notice, and the footage looks terrific.