Informal; most often appears in the phrasal verb "oomph up," meaning to add energy, style, or impact.
We need to oomph up the presentation before tomorrow’s meeting.
Nous devons booster la présentation avant la réunion de demain.
Used informally as an exclamation imitating a grunt or the sound/impact of a blow, or indicating sudden effort, pain, or surprise.
Ouf !Pour l'effort, le choc soudain ou la surprise. "Oomph!" he grunted as he lifted the heavy box.
"Ouf !" grogna-t-il en soulevant la lourde boîte.
Aïe !Pour exprimer la douleur.