A relational symbol denoting asymptotic equivalence or proportionality between functions in analysis and number theory.
Examples
Asymptotic equivalence of functions
n^2 + 3n \asymp n^2 \text{ as } n \to \infty
Asymptotic comparison of sequences
\{n^2\} \asymp \{(n+1)^2\}
Asymptotic behavior in analysis
\sin(x) + x^2 \asymp x^2 \text{ for large } x