inaudible

[ in-aw-duh-buh l ]

/ ɪnˈɔ də bəl /

not audible; incapable of being heard.

Origin of inaudible

First recorded in 1595–1605; in-³ + audible

in·au·di·bil·i·ty, in·au·di·ble·ness, noun in·au·di·bly, adverb

Some said their prayers, while others cursed the Yankees inaudibly, of course.

History of Kershaw's Brigade |D. Augustus Dickert
Insensibly and inaudibly my soul speaks to its own, and prepares it even now.

Zanoni |Edward Bulwer Lytton
“Good-night, Adelaide,” I said, inaudibly; and she loosed my hand.

The First Violin |Jessie Fothergill
A woman stands in my way, he inaudibly muttered with clinched teeth.

An Oregon Girl |Alfred Ernest Rice

The restless lips twitched constantly, mumbling fresh treason, inaudibly.

The Backwash of War |Ellen N. La Motte

inaudible

/ (ɪnˈɔːdəbəl) /

not loud enough to be heard; not audible

inaudibility or inaudibleness, noun inaudibly, adverb