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Related to frustule: diatom


 (frŭs′cho͞ol, -tyo͞ol)
The hard, siliceous bivalve shell of a diatom.

[French, from Latin frūstulum, diminutive of frūstum, piece broken off.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Botany) botany the hard siliceous cell wall of a diatom
[C19: from French, from Late Latin frustulum a small piece, from frustum a bit]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈfrʌs tʃul)

the shell of a diatom.
[1855–60; < French < Late Latin]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Crawford, "The fine structure of the frustule of melosira varians C.
Diatomaceous earth, also known as diatomite, is a fossil material of sedimentary origin, formed over centuries by siliceous skeleton (called "frustule") of aquatic unicellular microalgae, the diatoms, deposited on bottom of lakes or present in marine environments.
The most striking feature of the diatom is its elaborate frustule made up of grotesque amorphous silicon.
Cell solitary frustule twisted along the apical axis, panduriform; keeled raphe in each valve; plastids two and large.
Natural counting units were defined as one unit for each colony, filament, diatom frustule (regardless if colonial or filamentous) or unicellular algae.
Features Observed Weber (1970) Chloroplast 1-2 several Frustule diameter ([micro]m) 3-4,5 3-4 Pervalvar axis ([micro]m) 6-10 4-8 Areolae in 10 [micro]m 8 - Number of processes 5 -7 5-8 Rimoportula 1 - Features Hasle & Evensen Belcher & Swale (1976) (1978) Chloroplast Frustule diameter ([micro]m) 1-2 (4) 1-2 Pervalvar axis ([micro]m) 3-4 3-4 Areolae in 10 [micro]m - 6-10 Number of processes - 8 Rimoportula 6-8 5-6 1 1
Diatoms are a unique algal group because they are surrounded by a hard, silica-rich shell called a frustule that often has an incredibly intricate and delicate structure.