18-letter words containing p, h, e, n, y, l
- sling psychrometer — a psychrometer so designed that the wet-bulb thermometer can be ventilated, to expedite evaporation, by whirling in the air.
- the encyclopedists — the writers of the French Encyclopedia (1751-72) edited by Diderot and d'Alembert, which contained the advanced ideas of the period
- whispering gallery — a space or gallery beneath a dome or broad arch in which low sounds produced at any of certain points are clearly audible at certain other distant points.
- wireless telephony — Now Rare. radiotelephony.