Metaphor
From the Simple English Wikipedia, the free encyclopedia that anyone can change
Metaphor is language we use to compare things, but without using "like" or "as" - because that would be a simile. Another sort of metaphor is a "conceptual metaphor".
A metaphor very often uses the verb "to be": "love is war", for example, not that a writer sees "love as war" (this is a simile). Poetry includes much metaphor, usually more than prose.
Idioms use metaphors, or are metaphors: for example, the English phrase to kick the bucket means to die.
Spam is an example that any email user knows about - this word was originally a metaphor, from "spam", a tinned meat people do not usually like. Servers putting unwanted email into somebody's inbox was similar to waiters putting unwanted spam into food. This was originally suggested by a Monty Python skit (funny scene). When we use a metaphor very often and we forget the old meaning, or forget that the two meanings are connected, this is a "dead metaphor".
Originally metaphor was a Greek word for "transfer". It came from meta ("change") and pherein ("carry"). So the word metaphor in English was a metaphor, too. Today in Greek, metaphor is a trolley (a thing that is pushed for carrying shopping or bags).