Definition of gad:
(interjection) :
an exclamatory interjection roughly equivalent to 'by God', 'goodness gracious', 'for goodness' sake'
(v) :
to move from one location to another in an apparently random manner; often as phrasal verb gad about
(n) :
a sharp-pointed object; a
goad; a pointed metal tool for breaking or chiselling rock, especially in mining
"1957 Twice a day a
'gad' of iron, i.e., a bloom weighing 1
cwt. was produced, which took from six to seven hours. — H.R. Schubert, History of the British Iron and Steel Industry, p. 146."