uxoricide - reached a peak in 1995 with 0.0000006992%, lowest point in 1943 with 0.0000002473%
teosinte 0.0000086142
ambidexterous 0.0000006182%
from now on, I am going to cheat.
On this page
http://testyourvocab.com/faq i found following link:
http://www.kilgarriff.co.uk/bnc-readme.html
PLease note, that despite using a list I am only trying words that I can understand without looking them up in a dictionary.
africanised 0.0000000800%
africanise 0.0000000603%
annualising 0.00000005564%
Unimaginatively 0.0000000550%
baitboxes 0.0000000589%
... to be continued ....