Who are these that fly
`uwph  (oof)
to cover (with wings or obscurity); hence to fly; also (by implication of dimness) to faint (from the darkness of swooning)
as a cloud
`ab  (awb)
an envelope, i.e. darkness (or density, 2 Chron. 4:17); specifically, a (scud) cloud; also a copse -- clay, (thick) cloud, thick, thicket.
and as the doves
yownah  (yo-naw')
a dove (apparently from the warmth of their mating) -- dove, pigeon.
to their windows
'arubbah  (ar-oob-baw')
a lattice; (by implication) a window, dove-cot (because of the pigeon-holes), chimney (with its apertures for smoke), sluice (with openings for water) -- chimney, window.