definition of
approximation

[1] #1 approximation n. [estimate, estimation, idea] an approximate calculation of quantity or degree or worth; "an estimate of what it would cost"; "a rough idea how long it would take". wn

[2] #2 approximation n. the quality of coming near to identity (especially close in quantity). wn

[3] #3 approximation n. an imprecise or incomplete account; "newspapers gave only an approximation of the actual events". wn

[4] #4 approximation n. [bringing close together] the act of bringing near or bringing together especially the cut edges of tissue. wn