to·lu or To·lu balsam 
(tə-l)
(tə-l)n.
Balsam of Tolu.
[Spanish tolú, after Tolú, a seaport of northwest Colombia.]
- photodynamics
- photodynamic therapy
- photoelectric
- photoelectrical
- photoelectrically
- photoelectric cell
- photoelectric effect
- photoelectron
- photoemission
- photoemission spectroscopy
- photoengrave
- photoengraver
- photoengraving
- photo-essay
- photo essay
- photo-essayist
- photo finish
- photoflash
- photoflood
- photofluorogram
- photofluorographic
- photofluorography
- photog
- photogelatin process
- photogene