Meckel's diverticulum is the rudiment of the embryonic yolk sac.
Examples of rudiment
rudiment
In turn, Berlin denounced Switzerland as a medieval rudiment and its people renegade Germans.
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Examples of his style include the rudiment-heavy fills on Hey Joe, which help to carry the song through a series of increasingly intense climaxes.
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He would often emphasize the flam, a drum rudiment in which both sticks attack the drumhead at almost the same time, giving a heavy thunderous sound.
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With many animals the canine teeth in the upper or lower jaw, or in both, are much larger in the males than in the females, or are absent in females, except sometimes a hidden rudiment.
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Even beyond recognition, the Athenians allotted the goddess value based on this pureness of virginity as it upheld a rudiment of female behavior in the patriarchal society.
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More examples
The elementary stages of any subject (usually plural); "he mastered only the rudiments of geometry"
The remains of a body part that was functional at an earlier stage of life; "Meckel's diverticulum is the rudiment of the embryonic yolk sac"
(rudimentary) being in the earliest stages of development; "rudimentary plans"
(rudiments) basics: a statement of fundamental facts or principles
A rudiment is one of the basic patterns used in rudimental drumming. These patterns form the basic building blocks or "vocabulary" of drumming, and can be combined in a great variety of ways to create drumming music.
Vestigiality describes homologous characters of organisms that have seemingly lost all or most of their original function in a species through evolution. These may take various forms such as anatomical structures, behaviors and biochemical pathways. ...
(The Rudiments) The Rudiments are a ska and punk band from the East Bay, California.
A fundamental principle or skill, especially in a field of learning (often in the plural); Something in an undeveloped form (often in the plural); A body part that no longer has a function; In percussion, one of a selection of basic drum patterns learned as an exercise
(rudimentary) of or relating to one or more rudiments; Basic; minimal; with less than, or only the minimum, necessary