"intercepting"
I think that the meaning of intercepting is no more ,no less that the one used by ICAO in DOC4444:
6.7.3 Arriving aircraft 6.7.3.1 TYPES OF OPERATIONS
f) radar vectoring is used to intercept the ILS localizer course or the MLS final approach track;
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6.7.3.2.3 When vectoring to intercept the ILS localizer course or MLS final approach track, the final vector shall
enable the aircraft to intercept the ILS localizer course or MLS final approach track at an angle not greater than 30 degrees and to provide at least 2 km (1.0 NM) straight and level flight prior to ILS localizer course or MLS final approach track intercept.
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6.7.3.2.6 When assigning the final heading to intercept the ILS localizer course or MLS final approach track, the
runway shall be confirmed, and the aircraft shall be advised of:
a) its position relative to a fix on the ILS localizer course or MLS final approach track;
b) the altitude to be maintained until established on the ILS localizer course or MLS final approach track to
the ILS glide path or specified MLS elevation angle intercept point; and
c) if required, clearance for the appropriate ILS or MLS approach.
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6.7.3.4 REQUIREMENTS AND PROCEDURES FOR DEPENDENT PARALLEL APPROACHES
6.7.3.4.1 Dependent parallel approaches may be conducted to parallel runways provided:
b) the aircraft are radar vectored to intercept the final approach track;
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8.9.3.6 Aircraft vectored for final approach should be given a heading or a series of headings calculated to close with the final approach track. The final vector shall enable the aircraft to be established in level flight on the final approach track prior to intercepting the specified or nominal glide path if an MLS, ILS or radar approach is to be made, and should provide an intercept angle with the final approach track of 45 degrees or less.
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8.9.4 Vectoring to pilot-interpreted final approach aid
8.9.4.1 An aircraft vectored to intercept a pilot interpreted final approach aid shall be instructed to report
when established on the final approach track.
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12.4.2.2 VECTORING FOR ILS AND OTHER PILOT-INTERPRETED AIDS
b) YOU WILL INTERCEPT (radio aid or track) (distance) FROM
(significant point or TOUCHDOWN);
g) TURN LEFT (or RIGHT) HEADING (three digits) [TO INTERCEPT] or [REPORT ESTABLISHED];
k) MAINTAIN (altitude) UNTIL GLIDE PATH INTERCEPTION;
m) INTERCEPT (localizer course or radio aid) [REPORT ESTABLISHED].
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"Does the clearance to "intercept ILS" mean "cleared for ILS" or just to "intercept the LOCALIZER"
ILS is ILS and Localizer is Localizer . Clearance to intercept ILS means LOC and GLI . Localizer is only Localizer.
Just a reminder : e.g. Westband in CDG you can find 3 ILS Approaches . The localizers of the CDG one's are separated by 1,6 NM. Then the third one (Le Bourget) is separated from the CDG south one by 1,4 NM. triple simultaneous approaches are allowed as soon as a 1000 foot separation is applied before LOC interception.
This does not means that coming from north or south, for one of those ILS your altitude is compatible with that one published on the IAP especially when you have to cross one of the other LOC to established on your's.
So if no conflicting traffic you may expect to receive a full ILS interception clearance, if conflicting traffic , just a LOC clearance at a different ( or may be similar) altitude. In that case "Follow the glide" or "Intercept ILS" will be given later.