Options terms glossary

Plain-language definitions of DTE, BTO/STO, strike, premium, ITM/OTM, IV, the Greeks, and more.

Options come with a lot of shorthand. Here are the terms you'll meet when logging a contract, in plain language, with the common synonyms. For the how-to, see Logging options trades.

The instrument

  • Call — an option that profits when the underlying rises. Also “call option.”
  • Put — an option that profits when the underlying falls. Also “put option.”
  • Underlying — the stock or ETF the option is based on (e.g. AAPL). In the form this is the Symbol.
  • Strike — the price at which the option can be exercised. Also “strike price” or “exercise price.”
  • Expiration — the date the contract expires. Also “expiry” or “expiration date.”
  • Premium — the price of the option, quoted per share. One contract covers 100 shares, so the cash amount is premium × 100 × contracts. In the form this is the Entry / Exit premium.
  • Contract — one option = 100 shares of the underlying (the “contract size” or “multiplier”). Your Contracts field is the number of these.

Opening and closing (order actions)

  • DTEDays To Expiration. Also “days to expiry” or “time to expiration.”
  • BTO — Buy To Open — open a long position by buying the option (you pay the premium, a debit). Also “going long” or “buying a call/put.” In the form this is Long.
  • STO — Sell To Open — open a short position by selling the option (you receive the premium, a credit). Also “writing” an option, “selling premium,” or “shorting.” In the form this is Short.
  • STC — Sell To Close — close a long position by selling it back. The exit for a BTO.
  • BTC — Buy To Close — close a short position by buying it back. The exit for an STO.

Moneyness & value

  • ITM — In The Money — the option has intrinsic value (call: underlying above strike; put: below).
  • ATM — At The Money — strike ≈ the underlying's current price.
  • OTM — Out of The Money — no intrinsic value yet (call: underlying below strike; put: above).
  • Intrinsic value — how far ITM the option is right now.
  • Extrinsic value — the rest of the premium: time + volatility. Also “time value.” It decays toward zero by expiration.
  • Break-even — the underlying price where the trade nets zero at expiry (call: strike + premium; put: strike − premium). Shown on the Option Plan card.

How a position ends

  • Exercise — the holder converts the option into the underlying stock at the strike.
  • Assignment — the short side is obligated to fulfill an exercise (deliver or buy the stock). The result is a stock position — log it as a separate trade.
  • Expire worthless — the option expires OTM at $0. A long loses the full premium; a short keeps it. The Expired worthless button records this.

Chain & quote terms

  • Bid / Ask — the best price buyers will pay / sellers will accept. Their gap is the spread.
  • Mid — the midpoint of bid and ask; a fair estimate of fill price. The chain picker fills this as your premium.
  • Volume — contracts traded today.
  • OI — Open Interest — contracts currently outstanding (a liquidity gauge). Distinct from volume.
  • IV — Implied Volatility — the market's expected volatility priced into the option. Higher IV = richer premium.

The Greeks (risk sensitivities)

  • Delta — how much the option price moves per $1 move in the underlying.
  • Gamma — how fast delta itself changes.
  • Theta — daily time decay (how much value the option loses per day, all else equal).
  • Vega — sensitivity to a 1-point change in implied volatility.
  • Rho — sensitivity to interest-rate changes (usually minor).

Structure

  • Debit vs credit — a debit trade costs you premium (BTO); a credit trade pays you premium (STO).
  • Covered vs naked — a short option backed by the underlying (or cash) is “covered”; unbacked is “naked.”
  • Leg — one option in a position. A multi-leg position (a spread, condor, straddle or calendar) combines several legs; Ledger of Alpha records up to eight of them as one trade — see Multi-leg option structures.

Ask the support assistant

Answers come from the Help Center articles on this site — it can explain how the app works, not how to trade.

Answers are generated from Help Center articles and can be incomplete. contact us

Still stuck? Tell us what happened, or email support@ledgerofalpha.com.

Options terms glossary — Ledger of Alpha Help