English to English Dictionary
English to English vocabulary, definitions, and idioms. Explore comprehensive definitions, pronunciations, grammatical contexts, and cultural origins.
Browse English by Letter(Filtered by Letter “O”)
Clear Letter FilterEnglish Words Starting with “O”
Showing 18 of 39 words/oʊks/ [oaks]
[noun] Plural form of oak; large trees or shrubs of the genus Quercus, noted for their hard wood and lobed leaves.
/əbˈdʒɛk.tər/ [objector]
[noun] A person who raises an objection or expresses formal opposition to something.
/əbˈsiː.kwi.əs.nəs/ [obsequiousness]
[noun] The quality of being excessively obedient, attentive, or servile to an annoying degree.
/ˌɒb.zəˈveɪ.ʃən/ [observation]
[noun] The action or process of closely observing or monitoring something or someone.
/ˌɒbzəˈveɪʃənəl ˈɛrər/ [observational error]
[noun] The difference between a measured value of a quantity and its true value, caused by factors related to the observer or the measuring instrument.
/əbˈsɪd.i.ən/ [obsidian]
[noun] A hard, dark, glasslike volcanic rock formed by the rapid solidification of lava without crystal growth.
/ˈɒbstəkəlz ˌoʊvərˈkʌm baɪ məˈriː kjʊˈriː/ [obstacles overcome by Marie Curie]
[noun] The collective systemic, social, and personal barriers—including gender-based exclusion from academia, financial instability, and health risks—that Marie Curie successfully navigated to achieve her scientific breakthroughs.
/ˌoʊ.ʃiˈæn.ɪk/ [oceanic]
[adjective] Relating to or occurring in the ocean; or, figuratively, vast and immense in scale.
/ˈɒd.ɪ.tiz/ [oddities]
[noun] Strange or peculiar items, features, or behaviors that deviate from what is considered normal or expected.
/ˌɒn ˈkɔːl/ [on call]
[idiom] Available to be summoned for work or duty, especially during hours outside of a regular schedule.
/ɒn rɪˈkwest/ [on request]
[idiom] Available or provided only if specifically asked for by someone.
/ˈwʌns/
[adverb] On one occasion only; a single time.
/wʌn ˈbɪl.jən/ [one billion]
[noun] The cardinal number equal to 1,000,000,000 (one thousand million, or 10^9).
/wʌn ˈaʊər ænd ˈfɔːrti sɪks ˈmɪnɪts/ [one hour and forty six minutes]
[noun] A specific duration of time equivalent to 106 minutes or 6,360 seconds.
/wʌn əv ðə səˈluːʃənz tuː ɛks ˈskwɛər tuː ɛks ˈfɪftɪn ˈzɪroʊ ɪz ɛks ˈθriː wɒt ɪz ðə ˈʌðər səˈluːʃən/ [one of the solutions to x² 2x 15 0 is x 3 what is the other solution]
[noun] An algebraic math problem asking for the remaining root of a quadratic equation given one known solution.
/wʌn sɛk/ [one sec]
[idiom] An informal request for someone to wait for a very short period of time.
/ˈoʊ.pən/ [open]
[adjective] Not closed, locked, or fastened; allowing access, passage, or view.
/ˈoʊ.pə.nər/ [opener]
[noun] A device or tool used for opening containers, such as cans, bottles, or letters.