What is the meaning of expression?

noun

• The feelings expressed on a person's face.
  • usage: "a sad expression"; "a look of triumph"; "an angry face"
  • synonyms: look, aspect, facial expression, face
• Expression without words.
  • usage: "tears are an expression of grief"; "the pulse is a reflection of the heart's condition"
  • synonyms: manifestation, reflection, reflexion
• The communication (in speech or writing) of your beliefs or opinions.
  • usage: "expressions of good will"; "he helped me find verbal expression for my ideas"; "the idea was immediate but the verbalism took hours"
  • synonyms: verbal expression, verbalism
• A word or phrase that particular people use in particular situations.
  • usage: "pardon the expression"
  • synonyms: saying, locution
• The style of expressing yourself.
  • usage: "he suggested a better formulation"; "his manner of expression showed how much he cared"
  • synonyms: formulation
• A group of symbols that make a mathematical statement.
  • synonyms: formula
• Genetics) the process of expressing a gene. (
• A group of words that form a constituent of a sentence and are considered as a single unit.
  • usage: "I concluded from his awkward constructions that he was a foreigner"
  • synonyms: construction, grammatical construction
• The act of forcing something out by squeezing or pressing.
  • usage: "the expression of milk from her breast"