Maritime intelligence has a language of its own, and the terms are easy to blur together. This glossary defines the concepts used across our resources in plain language, and links each to a fuller explanation where one exists. It is organized by theme rather than alphabetically, so related ideas sit together.
Sensing and detection
AIS (Automatic Identification System). The self-reported system through which vessels broadcast identity, position, course, and speed. It is the base layer of maritime tracking, accurate for cooperative traffic and voluntary by design. (See: What Is Maritime Domain Awareness.)
Imagery. Direct observation of the water from above, used to establish what is physically present regardless of what a vessel reports. Imagery is the enrichment layer added to the self-reported base.
SAR (synthetic aperture radar). Radar imaging that works day or night and through cloud, detecting hulls in conditions where optical imaging cannot. (See: What Is SAR and Why It Matters for Vessel Detection.)
EO (electro-optical) imagery. Imaging in visible light, providing visual detail and confirmation in clear daylight. (See: SAR vs Optical (EO) Imagery.)
RF (radio frequency) detection. Locating a vessel by the signals it emits rather than by any position it reports, useful when a vessel is quiet on AIS. (See: What Is RF Detection in Maritime Surveillance.)
Tip-and-cue. A collection model in which a detection tips the system and a sensor is then cued to image that specific target. Efficient for known targets, but reactive and with no record of what was never cued. (See: Tip-and-Cue vs Persistent Monitoring.)
Persistent monitoring. A collection model that observes an area broadly and continuously rather than target by target, building an archive that supports discovery and retrospective investigation. (See: Tip-and-Cue vs Persistent Monitoring.)
Tracking, identity, and analysis
Maritime domain awareness (MDA). The effective understanding of activity at sea that could affect security, safety, the economy, or the environment. (See: What Is Maritime Domain Awareness.)
Attribution. Establishing which specific vessel an observed hull is, by matching measured dimensions and features against records. (See: How to Verify Vessel Identity with Satellite Imagery.)
AIS gap. A period during which a vessel that normally transmits stops appearing in the AIS record. Gaps can be benign or deliberate, and context decides which. (See: How to Identify and Investigate AIS Gaps.)
Vessel of interest. A vessel flagged for closer examination because a combination of indicators suggests elevated risk. The designation prioritizes attention, it does not assert wrongdoing. (See: What Is a Vessel of Interest.)
Vessel risk profile. A consolidated assessment of one vessel’s identity, ownership, history, and behavior, kept current to support a risk decision. (See: How to Build a Vessel Risk Profile.)
Deception and concealment
Dark ship / going dark. A vessel that is not transmitting AIS. Going dark is voluntary and not inherently illicit, so significance depends on the vessel and the context. (See: How to Detect Dark Ships.)
AIS spoofing. Deliberate manipulation of AIS so a vessel broadcasts a false position or identity. (See: What Is AIS Spoofing.)
GNSS jamming and spoofing. Interference with the satellite positioning signals a vessel uses to know where it is. Jamming denies a fix; spoofing feeds a false one, which can then corrupt what the vessel reports. (See: GNSS Jamming and Spoofing at Sea.)
Flag of convenience. A registry a shipowner adopts in a country other than their own, often for cost or lighter oversight. Legal and common, and a concern only when used to weaken accountability. (See: What Are Flags of Convenience and Flag Hopping.)
Flag hopping. Repeatedly changing a vessel’s flag state to shed scrutiny and reset the paper trail. (See: What Are Flags of Convenience and Flag Hopping.)
Ship-to-ship (STS) transfer. Moving cargo directly between vessels at sea. Routine in many contexts, and a red flag when concealed. (See: How to Detect Ship-to-Ship Transfers.)
Deceptive shipping practices. The recognized set of techniques vessels use to hide illicit activity, from AIS manipulation to document fraud. (See: Understanding Deceptive Shipping Practices.)
Sanctions, compliance, and enforcement
Shadow fleet (dark fleet). A network of mostly aging tankers with opaque ownership and non-Western insurance, used to move sanctioned cargo outside mainstream oversight. (See: What Is the Shadow Fleet.)
Maritime sanctions evasion. The playbook of concealment used to keep restricted cargo moving by sea despite sanctions. (See: How Maritime Sanctions Evasion Works at Sea.)
Oil price cap. A sanctions mechanism that limits the revenue from Russian seaborne oil by conditioning access to Western maritime services on a maximum sale price. (See: Understanding the Russian Oil Price Cap and the Dark Fleet.)
Other terms
IUU fishing. Illegal, unreported, and unregulated fishing, an umbrella term for fishing that breaks the rules meant to keep stocks sustainable and waters lawfully managed. (See: What Is IUU Fishing.)
Exclusive Economic Zone (EEZ). The maritime zone, extending from a state’s coast, within which it has rights over resources including fisheries. Fishing there without authorization is a common form of illegal fishing. (See: What Is IUU Fishing.)
Looking for the bigger picture behind these terms? Start with What Is Maritime Domain Awareness, then follow the links above into the specific topics.
If your team needs maritime intelligence you can act on, request a demo and we will show you what that looks like in your area of interest.
