ELF - A mythical, supernatural being resembling but seen as distinct from humans.
FLU - Influenza.
FUN - Enjoyable, amusing.
LET - To allow to, not to prevent (+ infinitive, but usually without to).
NET - A mesh of string, cord or rope.
NUT - A hard-shelled seed.
TEN - A numerical value equal to 10; the number occurring after nine and before eleven, represented in Roman numerals as X, in Arabic numerals as 10, and in the hexadecimal system (base 16) as A.
FEN - A type of wetland fed by ground water and runoff, containing peat below the waterline.
FELT - A cloth or stuff made of matted fibres of wool, or wool and fur, fulled or wrought into a compact substance by rolling and pressure, with lees or size, without spinning or weaving.
FUEL - Substance consumed to provide energy through combustion, or through chemical or nuclear reaction.
LEFT - The opposite of right; toward the west when one is facing north.
TUNE - A melody.
LENT - Simple past tense and past participle of lend.
LUTE - A fretted stringed instrument, similar to a guitar, having a bowl-shaped body or soundbox.
FLUE - A pipe or duct that carries gaseous combustion products away from the point of combustion (such as a furnace).
FLUTE - A woodwind instrument consisting of a metal, wood or bamboo tube with a row of circular holes and played by blowing across a hole in the side of one end or through a narrow channel at one end against a sharp edge, while covering none, some or all of the holes with the fingers to vary the note played.
FLUENT - That flows; flowing, liquid.