at call —(also: on call) 1. (of a doctor, etc.) available if required:
Category: Confusing Phrases
At best vs At one’s best
at best—(introductory or parenthetical) even under the most favorable conditions:
At arm’s length vs Close at hand
at arm’s length—1. as far away from one as one can reach with the arm:
At any one time vs At any time
at any one time—on each separate occasion:
At any cost vs At any price
at any cost—regardless of how much effort or sacrifice is needed:
At an end vs At the end
Note: The expression is not equivalent in meaning to the phrase in the end—
At all hours vs At any hour
at all hours—continuously, especially at unusual or irregular times:
At all events vs In any event
Note: The expression is not equivalent in meaning to the phrase in either event—no matter which of two possibilities happens:
At a word vs In a word
at a word—following the word of command:
At a white heat vs In a dead heat
at a white heat—in a state of intense or extreme emotion:
At a walk vs In a walk
at a walk—at the ordinary gait:
At a time vs At one time
Note: The expression does not correlate in meaning with the phrase at times—now and then: