word, letter and alphabet?

[Ju]

1. May I know the relations between word, letter and alphabet?

2. Is alphabet a collection of letters according to what I searched from the old thread? Then how about a word?

Thank you.

[5jj]

Have you tried looking up these three words here?

[Ju]

Have you tried looking up these three words here?

The following are the definations of word, alphabet and letter found in Collins English dictionary. However, I am still not clear about the relations. Can you help?
Letter

any of a set of conventional symbols used in writing or printing a language, each symbol being associated with a group of phonetic values in the language; character of the alphabet

word

one of the units of speech or writing that native speakers of a language
usually regard as the smallest isolable meaningful element of the language, although linguists would analyse these further into morphemes related adjective lexical verbal


alphabet
a set of letters or other signs used in a writing system, usually arranged in a fixed order, each letter or sign being used to represent one or sometimes more than one phoneme in the language being transcribed

Thank you.

[5jj]

Alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZ
Letter: W
Another letter: O
Another letter: R
Another letter:D

Word: WORD

Can you see the relationship now?

[Ju]

Yes, I do. Thank you.