TILDE

noun Etymology: Spanish, from Medieval Latin titulus tittle Date: circa 1864 a mark ˜ placed especially over the letter n (as in Spanish señor sir) to denote the sound \\nʸ\\ or over vowels (as in Portuguese irmã sister) to indicate nasality, 2. the mark ~ used to indicate negation in logic and the geometric relation “is similar to” in mathematics, the mark ~ used to indicate an approximate value