There are two meanings listed in OED's entry for the adverb zealously, one of which is labelled obsolete. See ‘Meaning & use’ for definitions, usage, and quotation evidence.
How common is the adverb zealously?
About 0.6occurrences per million words in modern written English
1750
4.2
1760
4.2
1770
4.3
1780
4.2
1790
4.4
1800
4.5
1810
4.6
1820
4.8
1830
4.8
1840
4.6
1850
4.2
1860
3.8
1870
3.2
1880
2.6
1890
2.1
1900
1.8
1910
1.5
1920
1.3
1930
1.1
1940
1.0
1950
0.95
1960
0.81
1970
0.71
1980
0.63
1990
0.56
2000
0.52
2010
0.51
How is the adverb zealously pronounced?
British English
/ˈzɛləsli/
ZEL-uhss-lee
U.S. English
/ˈzɛləsli/
ZEL-uhss-lee
Where does the adverb zealously come from?
Earliest known use
Middle English
The earliest known use of the adverb zealously is in the Middle English period (1150—1500).
OED's earliest evidence for zealously is from around 1495, in the writing of R. Fitzjames.
zealously is formed within English, by derivation.
In a zealous manner; esp. with passionate enthusiasm, fervour, or dedication; (formerly also) †with intense, powerful or overpowering feeling (cf. zealn. 1b) (obsolete).
?1495
And agayn to take grete shame & conscyence whan we rede them to haue doon so zelously in goddys cause.
R. Fitzjames, Sermo Die Lune in Ebdomada Pasche (de Worde) sig. biv
1544
Thus haue ye the answere of god wherfore he geueth his blessinges to the wyked, commandinge vs not to folowe theyr stepes, nor yet zelously to enuye their prosperite, but paciently to abyde a lytle.
G. Joye, Present Consol. Sufferers Persecucion sig. C. iij
1575
At the first when the light of the gospel..began to appeare, many were zelously bent to godlines.
T. Vautrollier, translation of M. Luther, Comm. Epist. to Galathians f. 24v
1611
To professe it [sc. Religion] zealously.
M. Smith in Bible (King James) Transl. to Reader sig. A4
1645
Thy care is fixt, and zealously attends To fill thy odorous Lamp with deeds of light.
J. Milton, Sonnet ix, in Poems 50
1661
The chanslir is selusslie your frind.
in O. Airy, Lauderdale Papers (1884) vol. I. 92
1716
You all remember how zealously, a few Years ago, these very Men join'd in the Cry of the Danger of the Church.
Polit. State Great Britain October 404
1769
You zealously undertook the cause of that gallant army.
‘Junius’, Polit. Contest iii. 18
1879
We know how fond ants are of honey, and how zealously and unremittingly they search for food.
J. Lubbock, Scientific Lectures ii. 36
1886
A place..where there was no prospect of improvement, however zealously one worked.
W. Besant, Children of Gibeonvol. II.ii. v. 13
1926
He addressed himself zealously to the study of Turkish.
Times 31 August 14/5
1975
They have zealously guarded the right of expression.
Crisis November 369/3
2006
An ambitious nation zealously committed to overseas trade.
With resolute or steadfast purpose or intent; earnestly, unwaveringly, staunchly; (also) with fixed attention; intently, diligently. Obsolete (archaic…
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
zealously typically occurs about 0.6 times per million words in modern written English.
zealously 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 zealously, adv., 1750–2010
* 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
1750
4.2
1760
4.2
1770
4.3
1780
4.2
1790
4.4
1800
4.5
1810
4.6
1820
4.8
1830
4.8
1840
4.6
1850
4.2
1860
3.8
1870
3.2
1880
2.6
1890
2.1
1900
1.8
1910
1.5
1920
1.3
1930
1.1
1940
1.0
1950
0.95
1960
0.81
1970
0.71
1980
0.63
1990
0.56
2000
0.52
2010
0.51
Frequency of zealously, adv., 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.