zona radiata typically occurs fewer than 0.01 times per million words in modern written English.
zona radiata is in frequency band 2, which contains words occurring between 0.001 and 0.01 times per million words in modern written English. More about OED's frequency bands
Frequency data is computed programmatically, and should be regarded as an estimate.
Frequency of zona radiata, n., 1880–2010
* Occurrences per million words in written English
Historical frequency series are derived from Google Books Ngrams (version 2), a data set based on the Google Books corpus of several million books printed in English between 1500 and 2010.
The overall frequency for a given word is calculated by summing frequencies for the main form of the word, any plural or inflected forms, and any major spelling variations.
For sets of homographs (distinct entries that share the same word-form, e.g. mole, n.¹, mole, n.², mole, n.³, etc.), we have estimated the frequency of each homograph entry as a fraction of the total Ngrams frequency for the word-form. This may result in inaccuracies.
Smoothing has been applied to series for lower-frequency words, using a moving-average algorithm. This reduces short-term fluctuations, which may be produced by variability in the content of the Google Books corpus.
Decade
Frequency per million words
1880
0.042
1890
0.037
1900
0.033
1910
0.029
1920
0.019
1930
0.016
1940
0.013
1950
0.011
1960
0.0093
1970
0.0079
1980
0.0078
1990
0.0078
2000
0.0066
2010
0.0062
Originally published as part of the entry for zona, n.
zona, n. was first published in 1921; not fully revised.