Definition of "aspirate"

We now come to the so-called aspirate [h], which must be also classified as a fricative consonant.

1972, Leonard R. Palmer, Descriptive and Comparative Linguistics, page 50

But we must correct then twenty authors who have it in the compound απηθείν and απήθημα ; and not (as the aspirate would require it) åpnoelv and αφήθημα

a. 1742, Richard Bentley, letter to Dr. Mead

Scrape cells using a cell scraper and aspirate the resulting slurry into a 2.0-mL Eppendorf tube.

2003, Miep H. Helfrich et al., editors, Bone Research Protocols, page 430

There is no doubt that the uncertainty about the letter H, which much defaces English in some classes of the community, is due entirely to Norman influence, for Frenchmen could not aspirate. Three words—hour, honor, heir, with compounds of them such as hourly, honourable, heirship, and the like, are quite enough to puzzle people who find H sometimes sounded, sometimes not.

1887, James Frederick Hodgetts, Greater England, page 33

[…] and there was in Late Middle Bengali a tendency to drop aspiration of non-initial aspirate stops.

1926, Suniti Kumar Chatterji, The Origin and Development of the Bengali Language, volume 1, Calcutta University Press, page 261