Phleb/o or ven/o both are correct
Ven- means vein
Venectomy or phlebectomy is the medical term meaning surgical removal of a vein. -ectomy is the combining form meaning surgical removal.
The combining form for "gingivo-" is "gingiv/o-".
The combining form for dermatologist is dermat/o.
The combining form for potassium is kal/i.
The combining form meaning "one who specializes in" is "-ologist".
The combining form is that the prefix osteo- is added.
Combining form for shape
The combining form for imperfect is dysto-.
The combining form for sugar is "glyc/o".
The combining form for "flesh" is "sarc/o" or "sarc-".