What is the meaning of Agad?

Obsolete form of egad.

wall or fence braces installed at regular intervals

face

honour

surface

third-person singular past subjunctive of aigid

to go or come along; join

Connacht and Ulster form of agat: second-person singular of ag

immediately, straightaway

second-person singular of aig: at you

past participle of aga

immediately; at once

quickly; readily; forthwith

consumed immediately; finished at once

Source: wiktionary.org