anti-freezing - atomic formulae
- aperture
- aperture angle
- aperture card
- aperture correction
- aperture diaphragm
- aperture distortion
- aperture effect
- aperture illumination
- aperture mask
- aperture meter
- aperture response
- aperture sight
- aperture stop
- apex
- apex angle
- aphanitic
- apical aperture
- aplanatic
- aplanatic lens
- aplanatic magnifying lens
- aplanatic objective
- aplite
- apochromatic lens
- apochromatic objective
- apogeal velocity
- apogee engine
- apophyllite
- apophysis
- apothecaries
- apothecaries pound
- apparatus room
- apparent brightness
- apparent elastic limit
- apparent focus
- apparent impedance
- apparent inductance
- apparent lifetime
- apparent lift
- apparent motion
- apparent orbit
