Metaphor
figure of speech in which one thing is asserted to be another when it is in fact not so, based on properties of the latter that apply to the former, pointing to similarity
black sheep
Iron
visual metaphor
third rail
letting the cat out of the bag
New Testament military metaphors
Poster child
Powder keg
red flag
smoke and mirrors
spring
toothpaste tube theory
touchstone
Powder keg of Europe
You can't have your cake and eat it
melting pot
Nixon goes to China
Burning bush
The Glass Escalator
three crows
lame duck
Bad apple