hoffentlich
hopefully
Expresses the hope or wish that something specific will happen.
Hoffentlich verpasse ich den Zug nicht.
Hopefully I won't miss the train.

hopefully
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hopefully
Expresses the hope or wish that something specific will happen.
Hoffentlich verpasse ich den Zug nicht.
Hopefully I won't miss the train.

The word is derived directly from the verb 'hoffen' (to hope). The ending '-lich' turns it into an adverb that expresses hope, similar to how 'wahrscheinlich' (probably) comes from 'wahr scheinen' (to seem true).
Ich hoffe, du bist gesund. Hoffentlich bist du gesund.
I hope you are healthy. Hopefully you are healthy.
'Hoffentlich' (hopefully) can stand in two typical positions in the sentence. If it is in position 1, the conjugated verb follows directly after it. It can also stand after the verb within the sentence.
Hoffentlich ist das Wetter morgen gut.
Hopefully the weather will be good tomorrow.
'Hoffentlich' (hopefully) can also stand alone as a brief answer to a question to express a wish or hope.
„Wird dein Team heute gewinnen?“ – „Hoffentlich!“
"Will your team win today?" – "Hopefully!"
only
'nur' and 'hoffentlich' can both have to do with a wish, but only in a specific use. 'hoffentlich' directly says that you hope something will happen. 'nur' expresses this wish only in combinations like 'wenn nur ...' (if only ...) or 'wäre nur ...' (if only ... were ...). In those cases, the wish often sounds strong or impatient. They can be confused because both show hope in sentences like these. Outside this wish form, however, 'nur' usually means a limitation and not 'hopefully'.

Morgen ist der Arzt hoffentlich wieder in der Praxis.
Hopefully the doctor will be back at the practice tomorrow.
Wenn ihr nur rechtzeitig alle Daten für das Projekt geschickt hättet!
If only you had sent all the data for the project on time!