Many English words have their origins in other languages and can be divided into two categories: loan words and English words with foreign roots

Loan Words 

The English language has gone through many periods where cultural contact has resulted in many words being adopted into English. Loan words are words:

• borrowed by the speakers of one language from a different language.
• commonly added to a language when there is cultural contact between languages. 
• adopted by speakers who borrow words from another language into their native language.
• lexical and taken from another language as is. 
• where the spelling usually remains the same as the native language.
• that may not follow English spelling rules and patterns.
• continually being added to English.

Many loan words may initially be recognized as foreign by English speakers who hear or use them. However, some loan words become so common in English speech that many may not even realize they are loan words. 

English Words with Foreign Roots

If a word in English has roots from other languages that formed a new word in English it is an English word with foreign roots. There are many, many words in English with at least one or more morphemes (roots, prefixes, or suffixes) from another language. English words with foreign roots developed within English, and their spelling is based on English spelling patterns.

English Words with Latin Roots

The majority of English multi-syllable words have Latin roots and most multi-syllable words are not actually English words derived from Latin. In other words, they were created using a previously existing Latin morpheme.

The following English words are either derived from Latin directly or by way of another language such as French; however, they are not Latin words.

Since these English words are based on Latin, not taken directly from Latin, they aren't loan words. They are English words with Latin roots.

English Words with Greek Roots

English has thousands of words with Greek roots, including much of our technical vocabulary. In centuries past, Greek words and their meanings were used as the roots of new terms in English.

Knowing if an English word has been adopted into English as a loan word or if an English word is built from foreign roots helps students understand a word's etymology. Studying the etymology of a word provides clues to the spelling of many English words.