[quote]My Chambers Dictionary (from the Mother Country) does not include this word .../quote]

Interesting. My Chambers does have "nubbin": "(US)n. A small or undedeveloped ear of corn, fruit etc."

Paul, here are a few useful URLs:
http://www.dictionary.com
http://www.m-w.com
http://www.onelook.com
http://www.thesaurus.com

And, of course, you should also check out tsuwm's page - http://members.aol.com/tsuwm/
as well, his wwftd is well worth subscribing to -it's interesting how often discussions here will surface in his mailing list.