Compound- backflip.
back
backboardbackdropbackfieldbackfirebackhandbackhoebackgroundbacklashbackpackbackpedalbackroombacksidebackslashbackslidebackstopbacktalkbacktrackbackupbackwashbackyardbarebackbuybackcallbackcomebackdiamondbackfeedbackflashbackfullbackhalfbackhardbackhatchbackhorsebackhumpbackgivebackgreenbackkickbackoutbackpaperbackpaybackplaybackpullbackquarterbackrazorbacksticklebackrollbacksetbackslingbacktiebackthrowback
compound words
backpack, backbone, backwardsbackachebackbitingbackboardbackbreakingbackchatbackcombbackdatebackdropbackfieldbackfirebackgroundbackhandbackhoebacklashbacklogbackbitbackupbackrestbackroombackseatbacksidebackslashbackslidbackslidebackstairbackstopbackstabberbackstagebacksidebackstreetbacktalkbacktrackbackwashbackwoodsbackyardcompound words ending with back:barebackbuybackcomebackcallbackcutbackdrawbackfullbackfatbackfastbackhalfbackhunchbackfallbackflashbackfightbackfullbackgreenbackhatchbackhunchbackoutbackslingbacksoftbackquarterbackrazorbacksetbackswaybackslingbacktiebackthrowback
Compound- backflip.
Compound words containing back:backbitebackboardbackbonebackbreakingbackfirebackhandbackhoebackdatebackdoorbackfieldbackhandbackgroundbacklashbackslapperbacklashbackslashbackslidbacklogbackpackbackslidebackspacebackstabbingbackstopbackspinbackstretchbackstrokebacktrackbackupbackwoodsbackwardbackwashbackwaterbackyardbarebackbuybackcomebackcutbackdiamondbackfeedbackflashbackfullbackhalfbackhumpbackhunchbackoutbackpaybackplaybackquarterbackrazorbackrollbackslingbacktailbackthrowback
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back
backboardbackdropbackfieldbackfirebackhandbackhoebackgroundbacklashbackpackbackpedalbackroombacksidebackslashbackslidebackstopbacktalkbacktrackbackupbackwashbackyardbarebackbuybackcallbackcomebackdiamondbackfeedbackflashbackfullbackhalfbackhardbackhatchbackhorsebackhumpbackgivebackgreenbackkickbackoutbackpaperbackpaybackplaybackpullbackquarterbackrazorbacksticklebackrollbacksetbackslingbacktiebackthrowback
compound words
backpack, backbone, backwardsbackachebackbitingbackboardbackbreakingbackchatbackcombbackdatebackdropbackfieldbackfirebackgroundbackhandbackhoebacklashbacklogbackbitbackupbackrestbackroombackseatbacksidebackslashbackslidbackslidebackstairbackstopbackstabberbackstagebacksidebackstreetbacktalkbacktrackbackwashbackwoodsbackyardcompound words ending with back:barebackbuybackcomebackcallbackcutbackdrawbackfullbackfatbackfastbackhalfbackhunchbackfallbackflashbackfightbackfullbackgreenbackhatchbackhunchbackoutbackslingbacksoftbackquarterbackrazorbacksetbackswaybackslingbacktiebackthrowback
Yes, "background" is a compound word, consisting of the words "back" and "ground" combined to form a single word with its own meaning.
No, the word battery is not a compound word. A compound word is two words to form a new word (example: back+wash).
Compound words are made by putting two words together. Examples: every + day = everyday back + ground = background eye + brow = eyebrow birth + day + birthday
Yes, into and today are compound words.
Compound words that have when in them are whence, whenever, and whensoever.