Metaphasis

'Oxford's great metaphasiarch', as Punch once called him, was seldom guilty of metaphasis, or the transposition of sounds. What he transposed was ideas.

Dr. Ashok suffered from a mild form of metaphasis. He made Spoonerisms.

But couldn’t it be that there is a distinction to be made between ‘metaphasis’ and ‘metathesis’? The OED defines the latter as ‘the interchange of position between sounds or letters in a word’ (my italics). An example would be Old English bridd becoming modern bird. This leaves ‘metaphasis’ free to describe what Spooner did: transpose sounds between different words, like his classic ‘our queer Dean’.

The technical term for this transposition is metaphasis.

The sister chromatid exchange (SCE) assay measures the drug-induced metaphasis SCE.

The reason is that homologous pairing takes place before metaphasis, during pachytene.

The nuclei at the 9.55 stage show some indication of change, but none of them have reached the metaphasis of the process of division, while at 11.25 the metaphasis was finished and the protoplasm already aggregated round the daughter nuclei.

There is abrupt lateral bending of the medial cortex wall of the proximal tibial metaphasis and, in the older child, deformity and retarded development of the ipsilateral epiphyseal plateau68