1. superlative form of fearful; most full of fear or anxiety
Usage: archaic or literary superlative; modern English typically uses 'most fearful'
2. superlative form of fearful; most causing fear or dread
Usage: archaic or literary superlative; modern English typically uses 'most fearful'

Examples

• The fearfullest moment of her life came when she heard the crash.
• He was the fearfullest of all the soldiers before battle.
• That was the fearfullest storm the town had ever witnessed.
• She gave the fearfullest cry when she saw the accident.
• The fearfullest part of the journey lay ahead of them.