public String unalias(String aliasOrField) {
        if (aliases == null || aliases.isEmpty()) return aliasOrField;
        String field = aliases.get(toLowerCase(aliasOrField));
        if (field != null) return field;
        return aliasOrField;
    }
Returns the field name of an alias or field name
container-search/src/main/java/com/yahoo/search/query/profile/types/QueryProfileType.java