lub dub
Lubb dubb corresponds to the heart sounds heard during systole and diastole, respectively.
HCA? I believe it's "lub" and "dup". (p. 493, under "heart sounds" heading...second sentence)
Heart sounds are noises generated by the beating heart from the flow of blood through it. Thump, boom can be used to describe it. Lub and Dub are also used. There are other sound words that suggest problems with the hearbeat as well.
Onomatopoeia
Heart sounds are created primarily from turbulence in blood flow created by the closures of the valves.
The word is spelled onomatopoeia. An onomatopoeia is a word that sounds like what it is describing. A good example of this is the word quack. The sound that a duck makes is "Quack." The word sounds like the sound it is describing.
what are fetal heart
Understanding Pediatric Heart Sounds was created in 2003.
Two sounds
Most people can hear two heart sounds per cycle - a quiet "lub" and a louder "dub". The "lub" sound is the contraction of the two atria, which results in the ventricles being filled with blood. The "dub" sound is the contraction of the two ventricles, which results in blood being forced into the arterial system. However, a trained physician can hear four sounds - the two described above, and two more that represent the sound of the valves opening back up after the contraction is over.
Onomatopoeia: Where sounds are spelled out as words; or, when words describing sounds actually sound like the sounds they describe. I heard him gurgling water.