Etymological doublets.

Etymological structure of the English vocabulary.

Native word-stems (man, pan).
Borrowings from latin (fanaticus — fan).
Scandinavian borrowings (sky) — 9-10century.
Borrowings from French (beggar, fiance) — Norman Conquest, 11century.
Borrowings from other languages (European, Oriental - feng shui, American Indians).

Etymological doublets.
Doublets are two words which were derived from the same basic word but by different routs. They differ in sound-form and meaning. The main source of etymological doublets in English is Latin language.
There are two reasons of the process:
1. One word was borrowed directly from Latin and the other – from French (major)
2. Words borrowed twice (discus → disc → dish, disk) (camera-chamber) (skirt-shirt)

Etymological hybrids
Hybrids are words that consist of etymologically different morphemes:
1. A native root + borrowed word-building morphemes ((to like – to dislike (Latin))
2. Borrowed root + native affix (peaceful (French))
3. Both elements are borrowed but from different languages (violinist (Italian+Greek))