ice crystals forming a white deposit (especially on objects outside)
frost
Verb
damage by frost
frost
Verb
cover with frost
frost
Verb
provide with a rough or speckled surface or appearance
frost
Verb
decorate with frosting
free energy
Noun
(physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work
flashover
Noun
an unintended electric discharge (as over or around an insulator)
flash flood
Noun
a sudden local flood of great volume and short duration
flashflood
Noun
a sudden local flood of great volume and short duration
floodhead
Noun
a wall of water rushing ahead of the flood
fohn
Noun
a warm dry wind that blows down the northern slopes of the Alps
food chain
Noun
(ecology) a community of organisms where each member is eaten in turn by another member
foehn
Noun
a warm dry wind that blows down the northern slopes of the Alps
food pyramid
Noun
(ecology) a hierarchy of food chains with the principal predator at the top
food web
Noun
(ecology) a community of organisms where there are several interrelated food chains
food cycle
Noun
(ecology) a community of organisms where there are several interrelated food chains
fair weather
Noun
moderate weather
fata morgana
Noun
a mirage of complex and elaborate buildings
fresh breeze
Noun
wind moving 19-24 knots
field of force
Noun
the space around a radiating body within which its electromagnetic oscillations can exert force on another similar body not in contact with it
force field
Noun
the space around a radiating body within which its electromagnetic oscillations can exert force on another similar body not in contact with it
field line
Noun
an imaginary line in a field of force
fine spray
Noun
precipitation in very small drops
fine structure
Noun
the presence of groups of closely spaced spectrum lines observed in the atomic spectrum of certain elements
firelight
Noun
the light of a fire (especially in a fireplace)
fluorescence
Noun
light emitted during absorption of radiation of some other (invisible) wavelength
fogbank
Noun
a large mass of fog on the sea (as seen from a distance)
forked lightning
Noun
a form of lightning that moves rapidly in a zigzag path with one end divided (fork-like)
friar's lantern
Noun
a pale light sometimes seen at night over marshy ground
frost heave
Noun
upthrust of ground or pavement caused by the freezing of moist soil
frost heaving
Noun
upthrust of ground or pavement caused by the freezing of moist soil
fresh gale
Noun
wind moving 39-46 knots
force per unit area
Noun
the force applied to a unit area of surface
ferrimagnetism
Noun
a phenomenon in ferrites where there can be incomplete cancellation of antiferromagnetic arranged spins giving a net magnetic moment
ferromagnetism
Noun
phenomenon exhibited by materials like iron (nickel or cobalt) that become magnetized in a magnetic field and retain their magnetism when the field is removed
fume
Noun
a cloud of fine particles suspended in a gas
fume
Verb
to be wet with sweat or blood, as of one's face
fume
Verb
to be mad, angry, or furious
fume
Verb
to treat with fumes, expose to fumes, especially with the aim of disinfecting or eradicating pests
fume
Verb
to emit a cloud of fine particles
frost snow
Noun
small crystals of ice
frost mist
Noun
small crystals of ice
facula
Noun
a large bright spot on the sun's photosphere occurring most frequently in the vicinity of sunspots
facula
Noun
a bright spot on a planet
fundamental interaction
Noun
(physics) the transfer of energy between elementary particles or between an elementary particle and a field or between fields