This event will be a datemark in our patriotic annals and in the progress of the nation.    From Wordnik.com.  [The Story of The American Legion] Reference

Just a week after these events, that is, the Wednesday after my great sermon, which is now a respectable landmark, or datemark, at Kilronan, I got the first letter from Bittra.    From Wordnik.com.  [My New Curate] Reference

Analysis of the digital photo showed that the datemark had been inserted with image editing software, while file data suggested it had been edited before the altercation took place.    From Wordnik.com.  [The Earth Times Online Newspaper] Reference