Revelation 21:8 New International Version
But the cowardly, the unbelieving, the vile, the murderers, the sexually immoral, those who practice magic arts, the idolaters and all liars--they will be consigned to the fiery lake of burning sulfur. This is the second death."
to [the] cowardly
Adjective - Dative Masculine Plural
Strong's Greek 1169: Cowardly, timid, fearful. From deos; timid, i.e. faithless.
International Standard Version
Mark 4:39 Then he got up, rebuked the wind, and told the sea, “Calm down! Be still!” Then the wind stopped blowing, and there was a great calm. 40 He asked them, "Why are you such cowards? Don't you have any faith yet?"
Only three versions use the word cowards in https://biblehub.com/mark/4-40.htm. Most use words like afraid, fearful, etc.
Mark 4:40 He said to his disciples, "Why are you so afraid? Do you still have no faith?"
Were they cowards?