Unuttered in a sentence as an adjective

His writings must be carefully studied line by line, and his unuttered thoughts must be read as distinctly as what he actually says. There are few thinkers so rich in unuttered thoughts.

It's a mashup of the two, and a phrase hitherto unuttered because it doesn't carry meaning. Put simply, the set of things that can be "in full force" generally does not include steamrollers.

Unuttered definitions

adjective

not made explicit; "the unexpressed terms of the agreement"; "things left unsaid"; "some kind of unspoken agreement"; "his action is clear but his reason remains unstated"

See also: unexpressed unsaid unstated unverbalized unverbalised unvoiced unspoken