Formidable and Grim

Formidable adjective - Requiring considerable physical or mental effort.

Grim is a synonym for formidable in frightful topic. In some cases you can use "Grim" instead an adjective "Formidable", when it comes to topics like ominous.

Nearby Word: formidably

Grim adjective - Harsh and threatening in manner or appearance.

Formidable is a synonym for grim in terrible topic. Sometimes you can use "Formidable" instead an adjective "Grim", if it concerns topics such as frightful, ominous, hopeless.

Nearby Words: grimy, grimly, grimed