What is the meaning of Thogh?

Obsolete spelling of though.

analytic past indicative of togh

However, nevertheless, though.

Although, even though, in spite of the fact that.

Yet, but, though, conceding that.

(Even) if, whether [with correlative]

Because, since, for the reason that.

That [following a negative, usually in an expression of surprise containing wonder]

When, at the moment that.

alternative form of þou (“thou”)

Source: wiktionary.org