A simile is a metaphor is identified by 'like' or 'as'.
- It's been a hard day's night, and I've been working like a dog - Beatles
- hands as cold as ice
- dinner tasted like garbage
We use similes all the time in order to make our words more descriptive, or to emphasise the effect or vividness of the description. There are also a lot of colloquial similes that use irony or sarcasm:
- as clear as mud
- like watching paint dry
Allusion is the term used to describe the suggestion of something without actually saying it (inferred), or a direct link to a person, object or painting (etc.) outside of literature.
Perhaps the most famous indirect allusion is that of Captain Lawrence Oats, an English Antarctic explorer, who, during his last expedition was suffering from frostbite and gangrenous feet. He left the camp as an act of self-sacrifice, saying, "I am just going outside and may be some time".
In every day life, examples of allusion include:
- chocolate is my Achilles' Heel
- don't be a Romeo
- 15 minutes of fame
- forbidden fruit