1) Dark of colour.
The use of this as an adjective has been associated with Scotland more than with England, and in the sense of dark in colour it is said to be rare. In fact, it was used quite commonly in Yorkshire. The churchwardens of St Michael, Spurriergate, recorded payments in 1544-5 for candles to cast light of myrk mornynges, York and in 1619-21 a boundary between Easingwold and Huby followed the same hedge unto mirke nooke. It was used frequently in conjunction with ‘grey’, to describe horses: 1445 ‘a mare of myrkgray colour, trottant’, Bolton near Pocklington
1542 my bay horse and my yowne merke gray stage, Cleasby
1558 my yong dyrke [sic] gray gelding, Topcliffe. It probably had the same meaning in the river called Murk Esk, an affluent of the Esk, a name which is on record since 1230
1619-21 Et per aquam mirke eske usque ad Wheeledale Beck. Other place-names which contain ‘mirk’ as a specific element are Mirk Fell and Mirk Slack both listed by Smith and there was j ten. voc. Myrke Head in Harwood-dale, in the Ministers’ Accounts for 1540-47.