Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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English buy
Old English bycġan (inherited)
Middle English bien (inherited)
Middle English biggen (mention)
Middle English buggen (mention)
Proto-Germanic *bugjaną (inherited)
Proto-West Germanic *buggjan (inherited)
Gothic 𐌱𐌿𐌲𐌾𐌰𐌽 (cognate)
Proto-Indo-European *bʰūgʰ- (derived)
Proto-Indo-European *bʰeugʰ- (derived)
Dutch beugen (cognate)
Old Norse byggja (cognate)
Old Saxon buggian (cognate)
Old Saxon buggean (mention)
Scots by (cognate)

English aby (prefix)
English sell (link)
English swallow (link)
English buyer (suffix)
English rebuy (prefix)
English buying (suffix)
English buycott (blend)
English buy time (mention)
English buyback (compound)
English overbuy (prefix)
English buyeth (suffix)
English buyable (suffix)
English buydown (compound)
English multibuy (prefix)
English underbuy (prefix)
English prebuy (prefix)
English forbuy (affix)
English outbuy (prefix)
English buy into (mention)
English buy up (compound)
English bring-and-buy (mention)
English must-buy (compound)
English forebuy (prefix)
English buyest (suffix)
English buybull (mention)
English buyup (compound)
English buyability (suffix)
Kikuyu gũra (mention)
Sranan Tongo bai (derived)
Central Tarahumara ralá (link)
Tok Pisin baim (derived)