Any

'Em
definition: An obsolete or colloquial contraction of the old form hem, them.

'Em is a 3 letter word that begins with a ' and ends in an M

'Gainst (pr)
definition: A contraction of Against.

'Gainst is a 7 letter word that begins with a ' and ends in a T

'Mongst (pr)
definition: See Amongst.

'Mongst is a 7 letter word that begins with a ' and ends in a T

'Neath (pr)
definition: An abbreviation of Beneath.

'Neath is a 6 letter word that begins with a ' and ends in a H

's
definition: A contraction for is or (colloquially) for has.

's is a 2 letter word that begins with a ' and ends in an S

'Sblood (in)
definition: An abbreviation of God's blood; -- used as an oath.

'Sblood is a 7 letter word that begins with a ' and ends in a D

'Sdeath (in)
definition: An exclamation expressive of impatience or anger.

'Sdeath is a 7 letter word that begins with a ' and ends in a H

'Snails (in)
definition: God's nails
Or His nails that is the nails with which the Savior was fastened to the cross; -- an ancient form of oath corresponding to 'Od's bodikins (dim. of body i.e. God's dear body).
'Snails is a 7 letter word that begins with a ' and ends in an S

'Swounds (in)
definition: An exclamation contracted from God's wounds; -- used as an oath.

'Swounds is an 8 letter word that begins with a ' and ends in an S

'T is
definition: A common contraction of it is.

'T is is a 5 letter word that begins with a ' and ends in an S

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