وَيْلٌ (Woe): means destruction, but idiomatically, it is a valley in Hell. Here the two meanings are intended. Allah here (swt) is menacing, and when the threatening is from Allah (swt), it is absolutely true without any doubt and He (swt) is completely able to execute it.

لِّكُلِّ (to every): in general, but the moral lies in the general meaning, not in the specific reason.

هُمَزَةٍ (scorner): Who insults someone in front of his face, by mentioning his faults, behaviours or his social status.

لُّمَزَةٍ (mocker): Who insults someone behind his back, by a gesture with his eye or tongue or even by any action or any other.

Allah (swt) in this verse wants to indicate that this wrong attitude is done a lot until it became a habit in its does.

Then Allah (set) continues in describing this man who gossips, criticizes people, looks at their faults and follows their privacy.