Browse by letter

English Words Starting With B

10,030 entries — pick a word to see its definition, pronunciation, and usage.

Filter

Parts of speech

Noun Verb Adjective Adverb Plural noun Combining form Verb (transitive)Verb (intransitive)Verb (ambitransitive)

blastocyst
nounVery Low
/ˈblæstəʊsɪst/An early stage in the development of an embryo in mammals, a hollow ball of cells, which later implants in the uterine wall.
blastoderm
nounVery Low / Technical
/ˈblastə(ʊ)dəːm/A thin layer of cells forming the outer surface of a blastula, being the earliest stage of embryonic development in many animals.
blastodisc
nounvery_low
/ˈblæstə(ʊ)dɪsk/The small, circular, whitish area of cytoplasm containing the nucleus, located on the surface of the yolk in an avian or reptilian egg.
blastodisk
nounVery Low
/ˈblæstəʊˌdɪsk/The round, whitish area on the yolk of an egg where the embryo begins to form.
blastoff
nounverbC1
/ˈblɑːstɒf/The moment when a spacecraft or rocket begins its flight by igniting its engines and launching from the ground.
blastogenesis
nounVery Low (Specialist)
/ˌblæstə(ʊ)ˈdʒɛnɪsɪs/Reproduction or development by budding from a pre-existing organism or cell.
blastoma
nounC2
/blæˈstəʊmə/A type of cancerous tumor, typically aggressive and primitive, that arises from embryonic or immature cells.
blastomere
nounLow/Very Technical
/ˈblastə(ʊ)mɪə/A cell formed by the cleavage of a fertilized ovum during early embryonic development.
blastomycete
nounC2 / Very Rare / Technical
/ˌblastə(ʊ)ˈmʌɪsiːt/a fungus that reproduces by budding and is classified in the former taxon Blastomycetes, which included yeasts and similar fungi.
blastomycosis
nounVery Low
/ˌblɑːstəʊmaɪˈkəʊsɪs/A fungal infection caused by inhaling spores of the Blastomyces fungus, primarily affecting the lungs but potentially spreading to other parts of the body.
blastopor
nounC2
/ˈblæstə(ʊ)pɔː/A highly specialized technical term in embryology referring to an opening in an early embryo.
blastopore
nounC2 (Very Low Frequency)
/ˈblæstə(ʊ)ˌpɔː/The initial opening of the primitive digestive tract in an embryo at an early stage of development.
blastosphere
nounVery low (Technical/Highly Specialised)
/ˈblæstə(ʊ)ˌsfɪə/An early embryonic stage, typically a hollow ball of cells (blastomeres) surrounding a fluid-filled cavity (blastocoel).
blastospore
nounRare/Very Low
/ˈblæstəʊˌspɔː/A spore formed by budding, as in certain fungi and yeasts.
blastostyle
nounVery Rare (C2+ Technical/Scientific)
/ˈblæstəʊstaɪl/In zoology, a delicate, rod-like internal structure in certain colonial hydrozoans (like Obelia) that produces and nourishes buds or medusae.
blastula
nounC2 (Proficient) / Specialized
/ˈblæstjʊlə/An early-stage embryo consisting of a spherical layer of cells surrounding a fluid-filled cavity, forming after cleavage of the fertilized egg.
blastulation
nounC2
/ˌblæstjʊˈleɪʃən/The process in early embryonic development where a single layer of cells (the blastula) forms around a fluid-filled cavity called the blastocoel.
blat
nounverbverb-intransitive+1C2
/blat/to make a loud, harsh noise or cry; also, to state something openly and loudly.
blather
nounverbverb-ambitransitiveC1/C2
/ˈblæð.ər/To talk at length in a foolish, trivial, or nonsensical way.
blatherskite
nounVery Low
/ˈblaðəskʌɪt/A person who talks nonsense or speaks in a foolish, long-winded manner.

Showing 5341–5360 of 10030 words.