- AAA
- ABA Number
- Absolute Amount Fee
- Absolute Markup
- Accelerator/Decelerator Indicator
- Access Rights
- Access Rights Group
- Account Alias
- Account Default Match Method
- Account Management
- Account Menu
- Account Transfer Online Notification (ATON)
- Accredited Investor
- Accretion
- Accrual
- Accrued Interest
- Accumulate/Distribute Algo
- Accumulation Phase
- Accumulation Swing Index
- Accumulation/Distribution Line
- ACES
- ACH Credit Only
- ACH Debit & Credit
- Active Dual Authorizer
- ActiveX in Excel
- Activity Downloads
- Activity Flex Query
- Activity Panel
- Activity Statements
- Actuals
- Ad Valorem Tax
- Adaptive Algo
- Adaptive Moving Average
- Add Liquidity Orders
- Adjust Average Price
- Adjust Position or Average Price
- Adjustable Rate Mortgage (ARM)
- Adjustable Stop Order
- Adjustment
- Administrator Accounts
- Administrator Marketplace
- ADR Conversion
- Advance-Refunded Bonds
- Advanced Orders Panel
- Advisor
- Advisor Portal
- Advisor-Managed Account
- ADX/DMI Indicator
- Affiliate
- After Hours Scanner Snapshot
- Agency Securities
- Aggregate Demand
- Aggregate Supply
- Aggregation
- Agricultural Commodity
- Agricultural Trade Option
- Agricultural Trade Option Merchant
- Alert Notification
- Alerts and Notifications
- Algo
- Algorithmic Execution Venue
- All or None Order
- Allocation Effect
- Allocative Efficiency
- Alpha
- Alpine Device
- Altcoin
- Alternative Minimum Tax
- Alternative Trading System (ATS)
- American Depository Receipt (ADR)
- American-Style Option
- Amortization
- Analyst Actions
- Analyst Ratings (Summary)
- Analyst Research
- Anchor Window
- Animal Testing
- Annual Net Income
- Annualized Rate
- Annuitization Phase
- Annuity Contract
- Anonymous Bidding
- Application Programming Interface (API)
- Apply to Entire Account Family
- Approved Delivery Facility
- Arbitrage
- Arbitration
- ArbTrader
- Arnaud Legoux Moving Average
- Aroon Oscillator Indicator
- Aroon Up/Down Indicator
- Arrival Price
- Arrival Price Algo
- Artificial Price
- Asian Central Banks
- Asian Option
- Ask
- Ask Size
- Asset Allocation
- Asset Class
- Asset Class Distribution
- Asset-Backed Securities (ABS)
- Assignment (OCC)
- Associated Person (AP)
- Association
- At a Premium
- At Auction Order
- At-The-Money
- Attached Orders
- Attribution Effect
- Auction
- Auction Rate Security (ARS)
- AUD
- Audit Trails
- AUS 200
- Aussie
- Australian Securities Exchange
- Authorized Forex Dealer
- Authorizers
- Auto Trailing Stop
- Automated Clearing House (ACH)
- Automated Customer Account Transfer Service (ACATS)
- Automatic Billing
- Automatic Futures Rollover
- Availability
- Available for Trading
- Average Daily Trading Volume
- Average Life
- Average Maturity
- Average Price
- Average True Range Indicator
- Averaging Down
- Awesome Oscillator