weighten

Etymology
From.

Verb

 * 1)  To add or give weight to; make heavy
 * 2)  To give support or importance to; make weighty
 * 3)  To weigh down
 * 4)  To become heavy
 * 1)  To weigh down
 * 2)  To become heavy
 * 1)  To become heavy
 * 1)  To become heavy