rare. In 9 erron. expirent. [ad. L. ex(s)pīrant-em, pr. pple. of ex(s)pīrāre: see EXPIRE.] a. (See quot. 1846.) b. nonce-wd. A name for a supposed vessel in plants, which assists in evaporation or perspiration.
1836. I. Taylor, Phys. Th. Another Life (1858), 156. The Mechanical adjustment of parts, as seen … in the vessels, the absorbents, the expirents, the flower … the seed.
1846. Worcester, Expirant, one who expires [citing I. Taylor: but see prec. quot.].
So 1864. in Webster, and in later Dicts.
