toss up

Short definition from Wiktionary

Verb

1. 1
   To make a decision based on chance, for example by flipping a coin or rolling a dice.
2. 2
   To throw something upwards.
3. 3
   To produce, generate.
4. 4
   To post or upload.
5. 5
   To cook or prepare something quickly.
6. 6
   To casually mention as an idea.
7. 7
   To vomit.
8. 8
   To beat up, thrash.

Noun

1. 1
   A decision in which neither choice is clearly favorable or unfavorable, or for which the outcome does not matter.
2. 2
   Either of two outcomes that are equally likely.
3. 3
   The toss of a coin used to decide some issue.
4. 4
   a toss-up question