<botany> A secondary involucre, as the bracts subtending the secondary umbels in the family Umbelliferae. ... (19 Oct 1998) ... Found on http://www.encyclo.co.uk/local/20973
In·vol'u·cel noun [ Dim. of involucre , or involucrum : confer French involucelle .] (Botany) A partial, secondary, or small involucre. See Illust. of Involucre . Found on http://www.encyclo.co.uk/webster/I/93