brain or onion

STEM
WordClue
HEADmind, brain
MINDbrain
HARNSbrain
HEARTneurology - brain, cardiology - ?
LIVERneurology - brain, hepatology - ?
ORDERfungus or stop-loss
PARTYRepublican or Conservative
POWERsolar or of will
RIVERNeva or Mekong
TEETHneurology - brain, stomatology - ?
HELMETbrain bucket
REASONmind, brain
NEUROLOGYteeth - stomatology, brain - ?
VEGETABLEonion or leek
CARDIOLOGYbrain - neurology, heart - ?
CONCUSSIONtraumatic brain injury
HEPATOLOGYbrain - neurology, liver - ?
HIPPOCAMPUSpart of brain
STOMATOLOGYbrain - neurology, teeth - ?
ENCEPHALITISInflammation of the brain
STOMATOLOGYbrain - neurology, teeth - ?
MINDbrain, psyche