Note: Not freely productive – mostly appears in fixed/established compounds. The result is an い-adjective with a negative nuance.
Common established forms:
The suffix がましい attaches to nouns (and occasionally verb stems) to form い-adjectives meaning "resembling," "suggestive of," or "having the feel of" the base word. It almost always carries a negative or undesirable nuance, implying that something has an unpleasant quality reminiscent of the base noun.
Because がましい is not freely productive (you cannot attach it to just any noun), it is best learned through the fixed expressions where it appears:
Since がましい creates い-adjectives, it conjugates like any other い-adjective:
The key point about がましい is its critical or disapproving tone. When you describe someone's behavior as おしつけがましい押しつけがましい or おんきせがましい恩着せがましい, you are expressing that their behavior is unpleasant or socially inappropriate. This makes it unsuitable for neutral or positive descriptions.