Schüssler for some reason considers this word to be a variant of 貫 *kʷān 'to go through the center' - which is both semantically and phonetically improbable.
Other attested meanings are 'be clamoring' (within a reduplication and obviously onomatopoeic) and 'to pour'.
The basic meaning of the character is 'name of a river (Guanjiang)' (this is the gloss found in Shuowen); but during Early Zhou the only attested usage of it is for the homonymous 'thickly growing bushes', 'be clamoring' and 'to pour'.