(British English) if people or things are thick/thin on the ground, there are a lot/not many of them in a place为数众多（或不多）；数目巨大（或微小）；众多（或稀少）- Customers are thin on the ground at this time of year.一年里这个时节顾客很少。
- Security officers were thick on the ground during the King’s visit.国王访问期间，安全官员在现场戒备森严。
See also thick | ground | thin