Kāya-gatā-sati: 'awareness or mindfulness with regard to the body', refers sometimes e.g. Vis.M VIII, 2 only to the contemplation on the 32 parts of the body, sometimes e.g. M. 119 to all the various meditations comprised under the 'contemplation of the body' kāyānupassanā the 1st of the 4 'foundations of awareness or mindfulness', consisting partly in concentration exercises, partly in insight vipassanā exercises. On the other hand, the cemetery meditations sīvathika mentioned in the Satipatthāna M. 10 are nearly the same as the 10 contemplations of loathsomeness asubha-bhāvanā. of Vis.M VI, whereas elsewhere the contemplation on the 32 parts of the body is called the 'reflection on impurity' patikkūla-saññā
In such texts as: 'One thing, o Bhikkhus, developed and repeatedly practised, leads to the attainment of understanding. It is the contemplation on the body' A.I, the reference is to all exercises mentioned in the 1st Satipatthāna.
Vis.M VIII, 2 gives a detailed description and explanation of the method of developing the contemplation on the 32 parts of the body. This exercise can produce the 1st absorption only jhāna The stereotype text given in the Satipatthāna Sutta and elsewhere - but leaving out the brain - runs as follows:
And further, o Bhikkhus, the Bhikkhu contemplates this body from the soles of the feet upward, and from the tops of the hairs downward, with skin stretched over it, and filled with many impurities: 'This body has hairs of the head, hairs of the body, nails, teeth, skin, flesh, sinews, bones, marrow, kidneys, heart, liver, diaphragm, spleen, lungs, intestines, bowels, stomach, excrement, bile, phlegm, pus, blood, sweat, fat, tears, skin grease, spittle, nasal mucus, oil of the joints, and urine.
Vis.M VIII, 2 says By repeating the words of this exercise one will become well acquainted with the wording, the mind will not rush here and there, the different parts will become distinct and appear like a row of fingers, or a row of hedge-poles. Now, just as one repeats the exercise in words, one should do it also in mind. The repeating in mind forms the condition for the penetration of the characteristic marks. He who thus has examined the parts of the body as to colour, shape, region, locality and limits, and considers them one by one, and not too hurriedly, as something loathsome, to such a one, while contemplating the body, all these things at the same time are appearing distinctly clear. But also when keeping one's attention fixed outwardly i.e. to the bodies of other beings, and when all the parts appear distinctly, then all men and animals moving about lose the appearance of living beings and appear like heaps of many different things. And it looks as if those foods and drinks, being swallowed by them, were being inserted into this heap of things. Now, while again and again one is conceiving the idea 'Disgusting! Disgusting!' - omitting in due course several parts - gradually the attainment - concentration appanā-samādhi i.e. the concentration of the jhāna will be reached. In this connection, the appearing of forms... is called the acquired image uggaha-nimitta the arising of loathsomeness, however, the counter-image patibhāganimitta
Maha Thera Nyanatiloka. Manual of Buddhist Terms and Doctrines, Buddhist Publication Society, first edition 1952.