The words el, ell sound the same but have different meanings and spellings. Why do el, ell sound the same even though they are completely different words?
The answer is simple: el, ell are homophones of the English language.
The letter l.
Informal An elevated railway.
A wing of a building at right angles to the main structure.
A right-angled bend in a pipe or conduit; an elbow.
Any of several historical units of measure corresponding roughly to the length of the arm, especially the English measure equal to 45 inches (114 centimeters).
Variant of el1.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.
If they are spelled the same then they are also homographs (and homonyms); if they are spelled differently then they are also heterographs (literally "different writing").