Lexical Definition

‎צָפַף‎ tsâphaph (tsaw-faf') to whisper H:V
a primitive root

chatter, peep, whisper.

1) (Pilpel) to chirp, peep
1a) of birds
1b) of ghosts

See Greek: ἀντέπω · ἀσθενέω · γῆ · φωνέω

Usage: 4 forms in 4 verses
Form Translated As     In Verse(s)
תְּצַפְצֵֽף it will whisper Isa.29.4
וּמְצַפְצֵֽף and chirping Isa.10.14
הַֽמְצַפְצְפִ֖ים who whisper Isa.8.19
אֲצַפְצֵ֔ף I chirp Isa.38.14

Brown-Driver-Briggs

[‎צַפַף‎] verb Pilpel chirp, peep (onomatopoetic; Late Hebrew Pilpal id.; Jewish-Aramaic ‎צַפְצֵף‎ chirp; Arabic sparrow, etc.); — Imperfect 3 feminine singular ‎תְּצַפְצֵף‎ Isa 29:4, 1 singular ‎אֲצַפְצֵף‎ Isa 38:14 Participle ‎מְצַפְצֵף‎ Isa 10:14, plural ‎הַמְפְצְפִים‎ Isa 8:19chirp, peep:

1. of birds Isa 10:14 (figurative of conquered peoples); of mourning, ‎׳‎‎בְּסוּסאֲ֗֗֗צ‎ Isa 38:14 (|| ‎אֶהְנֶּה בַּיּוֺנָה‎).

2. of spirits, ghosts Isa 8:19 (+ ‎הַמַּהְגִּים‎), ‎׳‎‎מֵעָפָר אִמְרָתֵךְ תְּצ‎ Isa 29:4 (like a spirit's).

Brown-Driver-Briggs References

Book Refs
Isaiah 8:19 · 10:14 · 29:4 · 38:14