a hot number
1. A person who is very sexually attractive. I met a real hot number last night. I could barely take my eyes off of him!
2. Someone or something that is particularly trendy, popular, or fashionable at the moment. That new talking robotic doll is definitely a hot number going into the holiday season. The movie star has become a really hot number in the media lately.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
Also, hot stuff. Someone or something that is currently popular or fashionable; also, someone or something unconventional or daring. For example, That new song is going to be a hot number, or He really thinks he's hot stuff. These slangy expressions use hot in the sense of "recent" or "fresh," a usage dating from the 1300s, although hot stuff dates from the 1700s and hot number from about 1900.
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
1. n. an exciting piece of music. Now here’s a hot number by the Wanderers.
2. n. an attractive or sexy girl or woman. Who’s that hot number I saw you with last night?
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.