Phthirius

noun

Phthir·​i·​us ˈthir-ē-əs How to pronounce Phthirius (audio)
: a genus of lice of the family Pediculidae that contains the pubic louse (P. pubis)

Browse Nearby Words

phthiriasis
Phthirius
Phthirus
See all Nearby Words

Cite this Entry

“Phthirius.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/Phthirius. Accessed 31 Oct. 2025.

Copy Citation

Share

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

'Affect' vs. 'Effect'

Using Bullet Points ( • )

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

The Difference Between 'i.e.' and 'e.g.'

What’s the difference between ‘cemetery’ and ‘graveyard’?
See More

Popular in Wordplay

See More

Skibidi, Mog & More: Gen Alpha Slang

13 Wonderful Words That You're Not Using (Yet)

Ten More Words from Taylor Swift Songs

Why do we 'bury the lede?'

'Za' and 9 Other Words to Help You Win at SCRABBLE
See More

Popular

See More

'Affect' vs. 'Effect'

Skibidi, Mog & More: Gen Alpha Slang

13 Wonderful Words That You're Not Using (Yet)
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
different halloween monsters in silhouette
A Monstrous Vocab Quiz Words That Go Bump in the Night
See All