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Related to semidiurnal: ebbed


 (sĕm′ē-dī-ûr′nəl, sĕm′ī-)
1. Of, relating to, occurring, or performed during half a day.
2. Occurring or coming approximately once every 12 hours, as the tides.
3. Of or relating to the arc described by a celestial body between its meridian passage and its points of rising or setting.
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.


1. of or continuing during half a day
2. occurring every 12 hours
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌsɛm i daɪˈɜr nl, ˌsɛm aɪ-)

1. pertaining to, consisting of, or accomplished in half a day.
2. occurring every 12 hours or twice each day.
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 ?
The Suwannee River estuary is shallow (water depth <2.2 m below mean sea level), and has semidiurnal tides with a tidal range of 0.7 m.
Tides in and near the inlets of the APES are generally semidiurnal, with a mean vertical range of 5 cm when averaged across Pamlico Sound (Roelofs & Bumpus 1953) to 30 cm in Core Sound (Dudley & Judy 1973).
The tidal regime is semidiurnal, presenting a 2.2 m mean tidal range and a 5.4 m average depth (Lana et al, 2001).
directly observed groundwater level) into four components: barometric response (BAR), diurnal and semidiurnal tidal response (TID), low-frequency component (LFC), and high-frequency non-tidal residuals (HFR).
This area is an exposed sandy beach habitat (McLachlan, 1990) that experiences semidiurnal tides.
The maximum tidal range at the mouth of the Swan River Estuary is small, i.e., [less than or equal to] 0.8 m, and tides can be diurnal or semidiurnal, depending on the time of year (Spencer, 1956).
Larval dispersal was simulated using a Lagrangian scheme (Burwell 2001, Meyers & Luther 2008) composed of a forward Eulerian scheme with a very small time step (15 sec) relative to the dominant diurnal and semidiurnal tidal signals.
This estuarial area has a semidiurnal tidal regime with an extreme amplitude tide, 9.5 m spring tide and 5.4 m neap tides (Piccolo & Perillo, 1997).
Periodic diurnal and semidiurnal fluctuations related to tidal effects.
Tides were semidiurnal in the Gulf of Mexico, ranging 1.3 m in tidal level in the study area.
The tides here are semidiurnal, and the tidal range is about -0.2 to 0.9 m (mean low water).
Mean tidal ranges are 2.5 m at spring tide and 1.0 m at neap tide, with a semidiurnal tidal cycle (the tide gauge station is indicated as a black-filled square point in Fig.