From saraph; a live coal; by analogy lightning; figuratively, an arrow, (as flashing through the air); specifically, fever -- arrow, (burning) coal, burning heat, + spark, hot thunderbolt.
see HEBREW saraph
H7565. resheph
I. רֶ֫שֶׁף noun masculineHabakkuk 3:5 flame, fire-bolt; — absolute ׳ר Deuteronomy 32:24 +; plural רְשָׁפִים Psalm 78:48, construct ׳רִשְׁפֵ 76:4, רִשְׁמֵּי Song of Solomon 8:6; suffix רְשֶׁפֶיהָ 8:6; —
1 flame: ׳ר ׳ר אֵשׁ Song of Solomon 8:6 its flames (that is of קִנְאָה אַהֲבָה,) are flames of fire; ר ׳בְּנֵי Job 5:7 = sparks; ׳ר = pointed flame of lighting Psalm 78:48 ("" בָּרָד); ׳ר קָ֑שֶׁת 76:4 Sharp flames of the bow, figurative for arrows.
2 fire-bolt of ׳יְ brining pestilence and death, Deuteronomy 32:24 (compare Dr; "" מְרִירִי קֶטֶב), Habakkuk 3:5 ("" דֶּבֶר).