worsen

verb

Etymology: From Middle English wursnen; equivalent to worse + -en.

1. To make worse; to impair.

   “Near-synonyms: aggravate, exacerbate; degrade, deteriorate; see also Thesaurus:aggravate”

   “Global warming has worsened the weather.”

2. To become worse; to get worse.

   “The weather has worsened.”

   “During the day conditions worsened quickly—for example, a 2-6-0 on the Uckfield line suddenly encountered flood water high enough to enter its ashpan and extinguish its fire—until lock gates up-river at Barcombe gave way and a tidal wave rolled down the valley meeting head-on a spring tide rolling up from the coast.”

3. To get the better of; to worst.