adamantean

adamantean

(ˌædəˈmæntɪən)
adj
1. (Minerals) of or relating to adamant
2. extremely hard
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Thus, "shard" is Shakespearian; "soilure" and "immures" are in "Troilus and Cressida"; "adamantean" is from Milton; "femineity" is from Browning.