21-letter words containing d, o, i, t
- well-ordering theorem — the theorem of set theory that every set can be made a well-ordered set.
- wet collodion process — a photographic process, in common use in the mid-19th century, employing a glass photographic plate coated with iodized collodion and dipped in a silver nitrate solution immediately before use.
- whip-and-tongue graft — a graft prepared by cutting both the scion and the stock in a sloping direction and inserting a tongue in the scion into a slit in the stock.
- white-crowned sparrow — a North American sparrow, Zonotrichia leucophrys, having black and white stripes on the head.
- wildlife photographer — someone that specializes in taking photographs of wild animals, especially in their natural habitats, and plants
- window of opportunity — limited chance to do sth
- with one's bare hands — If someone does something with their bare hands, they do it without using any weapons or tools.
- word association test — a technique for determining a subject's associative pattern by providing a verbal stimulus to which a verbal response is required.
- word-association test — a psychological test in which the person being tested responds to a given word with the first word (or the first word in a specified category, such as an antonym) brought to mind
- xeroderma pigmentosum — a rare inherited disease characterized by sensitivity to ultraviolet light, exposure resulting in lesions and tumors of the skin and eyes.
- yellow-throated vireo — an olive-green vireo, Vireo flavifrons, of eastern North America, having a bright yellow throat and breast.