chirr

[chur] /tʃɜr/
verb (used without object)
1.
to make a characteristic shrill, trilling sound, as a grasshopper.
noun
2.
the sound of chirring.
Also, chirre, churr.
Origin
1590-1600; alteration of chirp
British Dictionary definitions for chirr

chirr

/tʃɜː/
verb
1.
(intransitive) (esp of certain insects, such as crickets) to make a shrill trilled sound
noun
2.
the sound of chirring
Word Origin
C17: of imitative origin
Word Origin and History for chirr
v.

c.1600, echoic of a grasshopper's trill. Related: Chirred; chirring.