1. reaching or causing to reach the maximum limit or capacity
Usage: present participle of 'max'; informal
2. spending money up to the limit of a credit card or account
Usage: informal; financial context

Examples

• She is maxing out her credit card with holiday shopping.
• The athlete is maxing her potential by training every day.
• He was maxing the volume on his speakers.
• They are maxing out their retirement contributions this year.
• The server is maxing its capacity with too many users online.
• She's maxing her efforts to finish the project on time.