Muḍṭarib is related to iḍṭirāb, with senses of movement, wavering and unrest. Its specialized Hadith meaning remains the definition already studied.
Muṣaḥḥaf is related to taṣḥīf, a mistake in reading.
1. Active participle: a word form describing one who performs an action; muḍṭarib has this form. Iḍṭirāb al-mawj refers to the movement of waves.
2. Ṣaḥafī: in this technical usage, someone who misreads; it does not mean a newspaper journalist here.