hot on

1

Also, hot for. Enthusiastic about, as in She's really hot on golf, or He's hot for another skiing vacation. This seemingly modern slangy usage was first recorded in 1667. Also see make it hot for.

2

Also, hot at. Very good, impressive, as in He's hot at anything involving numbers. This expression, first recorded in 1573, is frequently used in the negative, as in I'm not so hot at new computer programs.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.