term:

Entirety

entirety n

pl: -ties
1 : the state of being entire or complete [in its ]
2 : an undivided whole
;specif
: an interest in real property that cannot be divided compare moiety

by the entirety

also
by the entireties

: by a husband and wife with undivided interests in the whole estate and a right of survivorship [an estate held by the entireties] see also tenancy by the entirety at tenancy