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synchronic vs. diachronic

[sin-kron-ik, sing-] / sɪnˈkrɒn ɪk, sɪŋ- /
Sometimes synchronical

adjective

Linguistics.
  1. having reference to the facts of a linguistic system as it exists at one point in time without reference to its history.

    synchronic analysis; synchronic dialectology.

[dahy-uh-kron-ik] / ˌdaɪ əˈkrɒn ɪk /

adjective

Linguistics.
  1. of or relating to the changes in a linguistic system between successive points in time; historical.

    diachronic analysis.