Use 'justifiably' when someone's actions or feelings are supported by strong reasons or evidence. She was justifiably upset when her privacy was invaded.
Pro Tip 2/3
Emotional Weight
'Justifiably' often carries an emotional charge, showing that the speaker believes the action or belief is warranted. He felt justifiably proud of his children's achievements.
Pro Tip 3/3
Argument Strength
Use 'justifiably' to describe the strength and fairness of an argument or a claim. The team could justifiably argue they deserved the win after a tough game.