extremely tired in a nervous or slightly worried way after a lot of mental or physical effort

It was a stressful day at work and by 5.00 I was completely frazzled. 我今天工作非常紧张，5点钟的时候就精疲力尽了。

burned or dried out after being in the sun or cooking for too long

I'd only been in the sun a couple of hours and my back was frazzled. 我才在太阳地里两个小时，后背就快晒焦了。

By the time I remembered about the meat it was frazzled. 等我想起来的时候，肉已经烤焦了。