Can you explain which form you're talking about? Your description doesn't seem to fit a W-2, whose Box 14 is simply called "Other" (no a or b) and is often a catch-all for unusual figures that may OR may not be relevant to your tax return -- health insurance premiums, railroad retirement tax amounts, pre-tax contributions to state & local pension plans, employee contributions to state & local unemployment or disability programs, etc.
If it's from a W-2, it sounds more like Boxes 12a, b, c, d which if completed consist of BOTH one or more letters (meanings are listed in the W-2 employee instructions) AND a number described by those letters. The most common Box 12 letters are D (401(k) contributions) and DD (non-taxable value of employer health insurance), but there are many others such as J (non-taxable sick pay) which sounds closest to the situation you describe. (A few W-2s have ONLY a dollar amount after letter J in Box 12, with NO other dollar amounts anywhere on the W-2; generally those should NOT be entered in TurboTax or you won't be allowed to e-file.)
