" grimly "

[Adjective]  | "grim" | \ ˈgrim \

1: fierce in disposition or action : savage

2: stern or forbidding in action or appearance

3: somber, gloomy

Origin: before 12th century ;

 Middle English, "fierce, savage, terrifying, repellent, violent, severe," going back to Old English grimm "fierce, savage, harsh, severe," going back to Germanic *grimma-, from earlier *gremma- (whence also Old Frisian grim, grem "fierce, severe, frightening," Old Saxon grimm "fierce, hostile, severe," Old High German grim, grimmi, Old Norse grimmr), adjective derivative from the base of *grimman- "to rage" (whence Old English & Old Saxon grimman "to rage," Old High German grimmen), probably going back to *ghrem-ne-, nasal present from an Indo-European verbal base *ghrem- "roar, rage," whence Avestan graməṇt- "raging," Greek chremetízein "to neigh, whinny," chrémisan "(they) neighed"; with zero-grade ablaut Old Church Slavic vŭzgrĭmě "thundered, roared," Lithuanian grumiù, grumė́ti "to roar, thunder"; with o-grade ablaut Germanic *gram- (whence Old English, Old Saxon & Old High German gram "angry, hostile, fierce," Old Norse gramr "anger," Old English gremman, gremian "to anger, enrage," Old High German gremmen, Old Norse gremja, Gothic gramjan), Old Church Slavic gromŭ "thunder," Greek chrómos, chrómē (Hesychius) "kind of noise, snorting, neighing," chrómados "grinding of jaws" (cf. {see: |chromis|chromis});

  * Note : The base *ghrem- is most likely of onomatopoeic origin, with different semantic developments in the Indo-European branch languages.;

[Adverb]  | "grimly" 

[Adjective]  | "grim"