No definitions found for 'vacuum phototube'
Perhaps one of these:
vaccine point,
vacuum pump,
vaisnavism,
vaishnava,
vacuum bottle,
vision purple,
vaishnavism,
vaginopennous,
vacuum bag,
vacuum flask,
vis impressa,
vaso-inhibitory,
vax mips,
vacuum pan,
vacuum valve,
vacuum brake,
vacuum bomb