We found 20 dictionaries that define the word size up:

General (14 matching dictionaries)

1. size up: Longman Dictionary of Contemporary English
2. size up: Merriam-Webster
3. size up: Collins English Dictionary
4. size up: Vocabulary.com
5. size-up: Wordnik
6. size up: Wiktionary
7. size-up: Infoplease Dictionary
8. size-up, size up: Dictionary.com
9. size up: Rhymezone
10. size up: FreeDictionary.org
11. size up: Mnemonic Dictionary
12. size up: TheFreeDictionary.com

Business (2 matching dictionaries)

13. size up: Legal dictionary
14. size up: Financial dictionary

Computing (1 matching dictionary)

15. size up: Encyclopedia

Medicine (1 matching dictionary)

16. size up: Medical dictionary

Miscellaneous (1 matching dictionary)

17. size up: Idioms

Slang (1 matching dictionary)

18. size up: Urban Dictionary

Definitions from Wiktionary (size up) ▸ verb:  (idiomatic) To evaluate; to estimate or anticipate the magnitude, difficulty, or strength of something. ▸ verb:  To wear a larger size of clothing. Similar: take stock, scrutinize, assess, size, valuate, weigh up, appraise, measure, rate, estimate, more... Opposite: underestimate, undervalue, downplay Phrases: to size up, move a size up from, size someone up, size me up, more... Adjectives: level, superior, first class, fine, ranking, high-ranking, top tier, next level, topgallant, supreme, top-flight ▸ Words similar to size up ▸ Usage examples for size up ▸ Idioms related to size up ▸ Wikipedia articles (New!) ▸ Words that often appear near size up ▸ Rhymes of size up ▸ Invented words related to size up