diff --git a/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientRequestContext.java b/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientRequestContext.java
index fd10636..513bb07 100644
--- a/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientRequestContext.java
+++ b/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientRequestContext.java
@@ -202,8 +202,8 @@
      *
      * @param name the message header.
      * @param valuePredicate value must fulfil this predicate.
-     * @return {@code true} if and only if a header with the provided name exists having either the exact value or whose
-     * comma-separated header string contains value as a whole word.
+     * @return {@code true} if and only if a header with the given name exists, having either a whitespace-trimmed value
+     * matching the predicate, or having at least one whitespace-trimmed single value in a comma-separated list of single values.
      * @see #getHeaders()
      * @see #getHeaderString(String)
      * @since 4.0
diff --git a/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientResponseContext.java b/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientResponseContext.java
index 6482152..8ba64e1 100644
--- a/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientResponseContext.java
+++ b/jaxrs-api/src/main/java/jakarta/ws/rs/client/ClientResponseContext.java
@@ -94,8 +94,8 @@
      *
      * @param name the message header.
      * @param valuePredicate value must fulfil this predicate.
-     * @return {@code true} if and only if a header with the provided name exists having either the exact value or whose
-     * comma-separated header string contains value as a whole word.
+     * @return {@code true} if and only if a header with the given name exists, having either a whitespace-trimmed value
+     * matching the predicate, or having at least one whitespace-trimmed single value in a comma-separated list of single values.
      * @see #getHeaders()
      * @see #getHeaderString(String)
      * @since 4.0
diff --git a/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerRequestContext.java b/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerRequestContext.java
index 36056f3..fc34ff0 100644
--- a/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerRequestContext.java
+++ b/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerRequestContext.java
@@ -234,8 +234,8 @@
      *
      * @param name the message header.
      * @param valuePredicate value must fulfil this predicate.
-     * @return {@code true} if and only if a header with the provided name exists having either the exact value or whose
-     * comma-separated header string contains value as a whole word.
+     * @return {@code true} if and only if a header with the given name exists, having either a whitespace-trimmed value
+     * matching the predicate, or having at least one whitespace-trimmed single value in a comma-separated list of single values.
      * @see #getHeaders()
      * @see #getHeaderString(String)
      * @since 4.0
diff --git a/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerResponseContext.java b/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerResponseContext.java
index 186ef4e..b0829ff 100644
--- a/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerResponseContext.java
+++ b/jaxrs-api/src/main/java/jakarta/ws/rs/container/ContainerResponseContext.java
@@ -124,8 +124,8 @@
      *
      * @param name the message header.
      * @param valuePredicate value must fulfil this predicate.
-     * @return {@code true} if and only if a header with the provided name exists having either the exact value or whose
-     * comma-separated header string contains value as a whole word.
+     * @return {@code true} if and only if a header with the given name exists, having either a whitespace-trimmed value
+     * matching the predicate, or having at least one whitespace-trimmed single value in a comma-separated list of single values.
      * @see #getHeaders()
      * @see #getHeaderString(String)
      * @since 4.0
diff --git a/jaxrs-api/src/main/java/jakarta/ws/rs/core/HttpHeaders.java b/jaxrs-api/src/main/java/jakarta/ws/rs/core/HttpHeaders.java
index 8a4c0cc..2ab8e91 100644
--- a/jaxrs-api/src/main/java/jakarta/ws/rs/core/HttpHeaders.java
+++ b/jaxrs-api/src/main/java/jakarta/ws/rs/core/HttpHeaders.java
@@ -70,8 +70,8 @@
      *
      * @param name the message header.
      * @param valuePredicate value must fulfil this predicate.
-     * @return {@code true} if and only if a header with the provided name exists having either the exact value or whose
-     * comma-separated header string contains value as a whole word.
+     * @return {@code true} if and only if a header with the given name exists, having either a whitespace-trimmed value
+     * matching the predicate, or having at least one whitespace-trimmed single value in a comma-separated list of single values.
      * @see #getRequestHeaders()
      * @see #getHeaderString(String)
      * @since 4.0