noun \ik-ˈspresh-ən\

Definition of EXPRESSION

a : something that manifests, represents, reflects, embodies, or symbolizes something else <the first clinical expression of a disease> b (1) : the detectable effect of a gene; also : the sum of the processes (as transcription and translation) by which a gene is manifested in the phenotype <gene expression can be controlled by regulatory proteins that bind to specific sites on DNA—Mark Ptashne> (2) : expressivity
: facial aspect or vocal intonation as indicative of feeling
: an act or product of pressing out

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