The NET Rankings have a new metric this season called WAB

[MarquetteMike1977]

The NET Rankings have a new metric this season called WAB — Wins Above Bubble. It's used to evaluate how many more wins a team has compared to what an NCAA Tournament "bubble" team would be expected to have against the same schedule, using the NET Rankings as the basis for opponent strength.
Marquette is #2 in the nation in WAB

Googled this. In the NCAA NET rankings, "WAB" stands for "Wins Above Bubble," which is a metric used to evaluate how many more wins a team has compared to what an average "bubble" team would be expected to have against the same schedule, essentially measuring the strength of a team's resume against the expected performance of a marginal tournament contender based on their opponents' strength.
Key points about WAB:
Calculation: This metric is calculated by comparing a team's actual wins against the expected wins an average bubble team would have against the same schedule, using the NET rankings to determine opponent strength.
Purpose: WAB helps the NCAA selection committee assess how many more wins a team has than what would be expected from a team on the "bubble" of the NCAA tournament.
Origin: This metric is popularized by analytics website BartTorvik.com.