Jastrow, רָחַף 1

רָחַף (b. h.) to move, vibrate.
    Pi. - רִחֵף to move, hover, flatter. Ḥag. 15ᵃ (ref. to Gen. I, 2) כיונה שמְרַחֶפֶת על בניה וכ׳ like a dove that hovers over her young without touching them.