All 5 Uses

sinister
in
The Power and the Glory, by Cooke
(Edited)

She was not without a healthy young woman's relish for this sort of admiration; but Shade Buckheath's proposal came with so little grace, in such almost sinister form, that she scarcely recognized it.
Chpt 9 *

sinister = evil, harmful, or frightening
This thing somehow has a sinister look to me.
Chpt 20
As their eyes encountered, Hardwick caught his breath sharply; both felt that chill of the cuticle, that stirring at the roots of the hair, that marks the passing close to us of some sinister thing—stark murder, or man's naked hatred walking in the dark beside our cheerful, commonplace path.
Chpt 20
That this pet toy of the modern millionaire should be set to work out the crude vengeance of wild men in these primitive surroundings, crowded up on a little rocky path of these savage mountains, at the door of a cave spring-house—such a food-cache as a nomad Indian might have utilized, in the gray bluff against the sky-line—it took the breath with its sinister strangeness.
Chpt 24
Johnnie's fair face whitened at the sinister words.
Chpt 24

Definitions:

(1) (sinister)
evil or harmful; or making an evil or frightening impression
(2) (meaning too rare to warrant focus)
Much more rarely and only in very old usage, sinister can refer to the left side of something.