the likelihood of a thing occurring rather than not occurring
"The odds are against us winning if we don't start practicing sooner."
the ratio by which one better's wager is greater than that of another
"he offered odds of two to one"
The ratio of the probability of an event happening to that of it not happening.
"The odds in favor of rolling a six on a standard die are three to one against."
In plain English: Odds are the chances that something will happen compared to the chances it won't.
"The odds are that we will run into our old friends at the market today."
Usage: In everyday speech, use "odds" to describe the likelihood of something occurring, often phrased as "the odds are in my favor." Avoid using it to mean a single chance or opportunity, which is better expressed as a "chance" or "opportunity."
The word odds comes from the adjective odd, which originally meant uneven or strange. It entered English with the specific sense of an unpaired number that could not be matched in a set.