Silent Initial Letters: pn, ps, mn, pt

Pronounce Greek-derived words that begin with consonant pairs English cannot say.

Some Greek words begin with consonant pairs that English speakers do not pronounce together at the start of a word. In English, the first letter goes silent, but the spelling keeps it. Pn-: pneumonia (pneumon, 'lung'), pneumatic (pneuma, 'air' or 'breath'). Ps-: psychology (psyche, 'mind' or 'soul'), pseudonym (pseudes, 'false,' plus onyma, 'name'). Mn-: mnemonic (mneme, 'memory'). Pt-: pterodactyl (pteron, 'wing,' plus daktylos, 'finger'). Worked example: notice what happens when the root moves to the middle of a word. In 'mnemonic,' the m is silent.

In 'amnesia,' which shares the memory root, you pronounce both m and n, because the a- prefix gives the m a vowel to lean on. Similarly, the p is silent in 'pneumonia,' but in 'apnea' you hear it. Silent letters are not random. They preserve the root, which is why keeping the spelling helps you link 'mnemonic' and 'amnesia' as relatives.

• 1Initial pn, ps, mn, and pt lose their first sound in English.
• 2The silent letter preserves the Greek root.
• 3In the middle of a word, both letters are often pronounced.