chap
美[tʃæp] vt.& vi.（使）疼痛，变粗糙，皲裂
网络握手验证协议；质询握手身份验证协议；挑战握手身份验证协议；毛细裂纹
1 . Today the best tests are performed in the hospital .see chap . 17..
现在，本医院可提供最好的化验（见第17章）。
来自柯林斯例句
2 . Poor chap — he was killed in an air crash.
不幸的家伙，他死于空难。
来自柯林斯例句
3 . He's not a bad chap —quite human for an accountant.
这个家伙人不坏——就会计来说已经很有人情味了。
来自柯林斯例句
4 . Are you all right, old chap ?
你还好吗，老家伙？
来自柯林斯例句
5 . Martin is a quiet, contemplative sort of chap .
马丁是个不爱讲话、喜欢沉思默想的小伙子。
来自柯林斯例句
1.a boy or man;
that chap is your host
2.a long narrow depression in a surface
3.a crack in a lip caused usually by cold
4.(usually in the plural) leather leggings without a seat; joined by a belt; often have flared outer flaps; worn over trousers by cowboys to protect their legs
1.crack due to dehydration;
My lips chap in this dry weather
CHAP全称是PPP（点对点协议）询问握手认证协议 （Challenge Handshake Authentication Protocol）。该协议可通过三次握手周期性的校验对端的身份，可在初始链路建立时完成时，在链路建立之后重复进行。通过递增改变的标识符和可变的询问值，可防止来自端点的重放攻击，限制暴露于单个攻击的时间。