move to and fro; "The shy student lingered in the corner"
be undecided about something; waver between conflicting positions or courses of action; "He oscillates between accepting the new position and retirement"
the highest level or degree attainable; the highest stage of development; "his landscapes were deemed the acme of beauty"; "the artist's gifts are at their acme"; "at the height of her career"; "the peak of perfection"; "summer was at its peak"; "...catapulted Einstein to the pinnacle of fame"; "the summit of his ambition"; "so many highest superlatives achieved by man"; "at the top of his profession"