di·la·tor 
(dī-lātər, dīlā′-, dĭ-lā-)
(dī-lātər, dīlā′-, dĭ-lā-)n.
1. A muscle that dilates a body part, such as a blood vessel or the pupil of the eye.
2. An instrument that dilates a body part, such as a cavity, canal, or orifice.
- spectroheliogram
- spectroheliograph
- spectroheliographic
- spectroheliography
- spectrohelioscope
- spectrohelioscopic
- spectrometer
- spectrometric
- spectrometry
- spectrophotometer
- spectrophotometric
- spectrophotometry
- spectroscope
- spectroscopic
- spectroscopical
- spectroscopically
- spectroscopic analysis
- spectroscopic binary
- spectroscopist
- spectroscopy
- spectrum
- specula
- specular
- specularly
- speculate