1916 E. Sapir in 83 One of the most striking American examples of phonetic accord..is the occurrence in a considerable number of West Coast linguistic groups..of..glottalized (‘fortis’) stops.
1921 E. Sapir ix. 199 A ‘glottalized’ series of stopped consonants.
1933 L. Bloomfield vi. 101 Some languages have glottalized spirants (preceded, accompanied, or followed by a glottal stop).