abut on

listen to the pronunciation of abut on
İngilizce - Türkçe
İngilizce - İngilizce
To border on

Now the two bounding notes of an enharmonic tetrachord of the relevant sort will indeed both be the lowest notes of pykna when the tetrachords are put together in conjunction; but the higher of them can never abut on a pyknon in the case envisaged here, where the tone is introduced to disjoin the tetrachords.

border on, be right next to
abut on