The TRUNC() function takes a number and returns the first integer that is equal to or closer to zero than the argument:
TRUNC(5.5) === TRUNC(5.1) === TRUNC(5) === 5 TRUNC(-5.5) === TRUNC(-5.1) === TRUNC(-5) === -5
The TRUNC() function (v11.0+) takes a second optional parameter to indicate the number of digits to truncate to.
TRUNC(5.6789,2) === 5.67 TRUNC(-5.6789,2) === -5.67