Obs. [Echoic: cf. COO, CROOD.] = CROOD.

1

1611.  Cotgr., Roucoler, to croo like a Doue or Queest. Roucoulement, the crooing of Doues.

2

1706.  Phillips, To Croo or Crookel, to make a Noise like a Dove, or Pigeon.

3