
grimmig
grim
Having a very angry, dark, or relentless facial expression.
Der Trainer schaute seine Mannschaft nach der Niederlage grimmig an.
The coach looked grimly at his team after the defeat.
grim
Loading your saved state.

grim
Having a very angry, dark, or relentless facial expression.
Der Trainer schaute seine Mannschaft nach der Niederlage grimmig an.
The coach looked grimly at his team after the defeat.

bitter / severe
Describes very intense and unpleasant cold or strong pain.
Trotz des dicken Mantels spürte er die grimmige Kälte des Winters.
Despite the thick coat, he felt the bitter cold of winter.
The adjective 'grimmig' is closely related to the noun 'der Grimm', an old term for strong anger or rage. So someone who looks 'grimmig' (grim) shows their anger in their face.
Sein Gesichtsausdruck war voller Grimm.
His facial expression was full of rage.
You can easily recognize the meaning of 'grimmig' from the context. If it refers to a person, their gaze, or their face, it means 'angry' or 'grim'. If it describes the weather or pain, it means 'very intense and unpleasant'.
Der alte König blickte den Boten grimmig an.
The old king looked grimly at the messenger.
When referring to an angry facial expression, 'grimmig' is often combined with verbs of looking or with nouns for the face. Typical phrases are 'grimmig schauen' (to look grim), 'grimmig blicken' (to gaze grimly), or 'eine grimmige Miene' (a grim expression).
Mit grimmiger Miene verließ er den Raum, ohne ein Wort zu sagen.
With a grim expression, he left the room without saying a word.
In the meaning 'intense and unpleasant', 'grimmig' is used almost exclusively for cold or pain. Common combinations are 'grimmige Kälte' (bitter cold), 'grimmiger Frost' (severe frost), or 'grimmiger Schmerz' (severe pain).
Sie zitterte trotz ihrer dicken Jacke in der grimmigen Kälte.
She shivered in the bitter cold despite her thick jacket.
bitter
Bitter and grimmig can both describe very intense, unpleasant cold. Bitter emphasizes the penetrating effect of the cold and is a common collocation. Grimmig is more expressive and presents the cold as especially harsh and relentless.

Am Morgen herrschte eine grimmige Kälte, die das Dorf fest im Griff hatte.
A grim cold prevailed in the morning, holding the village firmly in its grip.
Am Morgen herrschte eine bittere Kälte, die durch jede Jacke drang.
Bitter cold prevailed in the morning, penetrating every jacket.