Write full name of LED.

Hint: The abbreviation of name is the short form of its full name. The abbreviation of any large name is created using initial letters of each word. Example: LASER is the abbreviation of light amplification by stimulated emission of radiation.

Complete step by step answer:
Semiconductor is the substance that neither belongs to metal or non-metals. The outermost shell of the semiconductor has 4 electrons. So, it can neither gain or lose 4 electrons to form ionic bonds. Thus, it forms a covalent bond by sharing electrons with other elements of the same semiconductor.
The semiconductor combines with 4 atoms of the same semiconductor known as pure intrinsic semiconductor. This intrinsic semiconductor is doped with either pentavalent or trivalent impurity to form p or n type of semiconductor respectively.
When the same semiconductor is doped with both trivalent and pentavalent impurity. So, half of the semiconductor becomes p type of semiconductor and the remaining half becomes n type of semiconductor. This is known as a p-n junction diode.
When the energy from the p-n junction diode is released in the form of light. The diode is known as a light emitting diode.
The full form of LED is Light emitting diode.

Note:
When the energy across the junction is emitted in the form of a wave of specific wavelength. The diode is known as the light emitting diode. The color of the LED is dependent on the frequency of the light.