Distribution in zones or regions of definite character; spec. in Ecology, the distribution of plants into specific zones which are characterized by their dominant species.
1898
The zonal constitution and disposition of plant formations. By Frederic E. Clements.
The author has here reviewed the phytogeographical contributions bearing upon the subject in hand, with especial reference to the part they have played in the elaboration of the conception of zonation. In addition, he has endeavoured to demonstrate the fundamental universality of zonation in all divisions of the floral covering.
Zonation in a habitat... The line that connects the points of accumulated or abrupt change in the symmetry is a stress line or ecotone... Ecotones are well marked between formations, particularly where the medium changes: they are less distinct within formations. It is obvious that an ecotone separates two different series of zones in the one case, and merely two distinct zones in the other.
F. E. Clements in Bot. Surv. Nebraska No. 7. 153
1926
Adjacent plant communities are often arranged in more or less definite zones, following one another in constant order. This is specially noticeable in ascending a mountain (where it is called altitudinal zonation).
A. G. Tansley & T. F. Chipp, Aims & Methods in Study of Vegetation iv. 53
1936
Reliable local zonation of both the Eocene and the Oligocene has been worked out in the Tampico area.
J. Muir, Geol. Tampico Region, Mexico 121
1969
Marine work during the first eight months concentrated on community structure and zonation on cliffs, reef flats and in mangrove woodland.
Nature 15 March 1005/2
1971
It is first necessary therefore to establish a regional metamorphic zonation.
Scottish Journal of Geologyvol. 7 306
1981
I would have preferred to have seen an accompanying annotated sketch so that the plant zonations could be easily recognised.
Biology. The evolutionary diversification of an animal or plant lineage into forms adapted to different habitats or ecological niches; = adaptive radi…
Formation of zones in the oocytes of certain plants and animals.
1899
There is a stage called zonation in which the nuclei, usually in metaphase, are lined up around the ooplasm.
Botanical Gazettevol. 28 237
1902
During the completion of the mitosis the ooplasm and periplasm become clearly differentiated, but as yet no plasmoderma exists. This process of differentiation has been termed zonation.
Botanical Gazette December 421
1975
The zonation of the ooplasm reveals that a majority of the oocytes [of the teleost Schizothorax richardsonii] have a darkly stained inner and a lightly stained outer zone.
Some consonants can take the function of the vowel in unstressed syllables. Where necessary, a syllabic marker diacritic is used, hence /ˈpɛtl/ but /ˈpɛtl̩i/.
Vowels
iːfleece
ihappy
ɪkit
ɛdress
atrap, bath
ɑːstart, palm, bath
ɒlot
ɔːthought, force
ʌstrut
ʊfoot
uːgoose
əletter
əːnurse
ɪənear
ɛːsquare
ʊəcure
eɪface
ʌɪpride
aʊmouth
əʊgoat
ɔɪvoice
ãgratin
ɒ̃salon
ᵻ(/ɪ/-/ə/)
ᵿ(/ʊ/-/ə/)
Other symbols
The symbol ˈ at the beginning of a syllable indicates that that syllable is pronounced with primary stress.
The symbol ˌ at the beginning of a syllable indicates that that syllable is pronounced with secondary stress.
Round brackets ( ) in a transcription indicate that the symbol within the brackets is optional.
Some consonants can take the function of the vowel in unstressed syllables. Where necessary, a syllabic marker diacritic is used, hence /ˈpɛd(ə)l/ but /ˈpɛdl̩i/.
Vowels
ifleece, happy
ɪkit
ɛdress
ætrap, bath
ɑlot, palm, cloth, thought
ɑrstart
ɔcloth, thought
ɔrnorth, force
ʊfoot
ugoose
əstrut, comma
ərnurse, letter
ɪ(ə)rnear
ɛ(ə)rsquare
ʊ(ə)rcure
eɪface
aɪpride
aʊmouth
oʊgoat
ɔɪvoice
ɑ̃gratin
æ̃salon
ᵻ(/ɪ/-/ə/)
ᵿ(/ʊ/-/ə/)
Other symbols
The symbol ˈ at the beginning of a syllable indicates that that syllable is pronounced with primary stress.
The symbol ˌ at the beginning of a syllable indicates that that syllable is pronounced with secondary stress.
Round brackets ( ) in a transcription indicate that the symbol within the brackets is optional.
Simple text respell breaks words into syllables, separated by a hyphen. The syllable which carries the primary stress is written in capital letters. This key covers both British and U.S. English Simple Text Respell.
Consonants
b, d, f, h, k, l, m, n, p, r, s, t, v, w and z have their standard English values
gguy
jjay
yyore
chchore
khloch
shshore
ththaw
dhthee
zhbeige
Vowels
atrap
ahpalm
airsquare
arstart
arrcarry (British only)
awthought
ayface
a(ng)gratin
edress
eefleece
eerdeer
errmerry
ikit
ighpride
irrmirror
olot (British only)
ohgoat
oogoose
oorcure
orforce
orrsorry (British only)
owmouth
oyvoice
o(ng)salon
ustrut
uhletter
urnurse
urrhurry
uufoot
Frequency
zonation typically occurs about 0.4 times per million words in modern written English.
zonation is in frequency band 4, which contains words occurring between 0.1 and 1 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 zonation, n., 1890–2010
* 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
1890
0.03
1900
0.037
1910
0.045
1920
0.064
1930
0.11
1940
0.17
1950
0.26
1960
0.37
1970
0.44
1980
0.45
1990
0.43
2000
0.41
2010
0.34
Frequency of zonation, n., 2017–2024
* Occurrences per million words in written English
Modern frequency series are derived from a corpus of 20 billion words, covering the period from 2017 to the present. The corpus is mainly compiled from online news sources, and covers all major varieties of World English.
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 corpus.
Period
Frequency per million words
2017
0.0063
2018
0.0095
2019
0.014
2020
0.023
2021
0.029
2022
0.039
2023
0.044
2024
0.047
zonation, n. was first published in 1921; not fully revised.