Across
1 first name of US president, civil war general (7)
3 Oppenheimer was director of this lab (3,6)
6 study of the origin of words (9)
8 gracefully; in an extremely beautiful and delicate manner (11)
11 minimum number of group for formal meetings (6)
Down
2 study of insects (10)
4 Little Orphan Annie song (8)
5 one "ar," two "efs," one gun, one badge (7)
7 sign that drivers occasionally encounter (5)
9 idyllic place; 1980 musical film with Olivia Newton-John (6)
10 surface on which Montreal Canadiens play (3)