Bit (5)
'bit' is the definition.
(synonyms)
This is all the clue.
(Other definitions for piece that I've seen before include "Firearm -- collector's item" , "Section; firearm" , "wedge a > bit" , "Unpleasant character" , "Separate part of a whole" .)
'bit' is the definition.
(I know that bit can be written as shred)
This is all the clue.
(Other definitions for shred that I've seen before include "just a touch" , "Thin scrap or strip" , "(Tear into) small piece(s)" , "Small piece torn from something" , "Scrap; finely tear" .)
'bit' is the definition.
(both can mean a small amount)
This is the entire clue.
(Other definitions for tad that I've seen before include "Smidgen" , "Small bit" , "Slight amount" , "A small amount (colloq.)" , "little boy" .)
'bit' is the definition.
(I know that bit can be written as iota)
This is all the clue.
(Other definitions for iota that I've seen before include "Extremely small amount" , "(Not one) little bit" , "Greek equivalent of the letter I" , "A little piece" , "Just a jot, from Greek alphabet" .)