out of one's depth
In over head
Beyond one's ability or understanding.
The phrase comes from water—if you're out of your depth, you can't touch bottom and may struggle to stay afloat.
Extended to any situation where someone lacks the necessary competence or knowledge: She was out of her depth in the advanced physics seminar.
He quickly realized he was out of his depth negotiating with seasoned lawyers.
- unfamiliarityLack of prior knowledge
- fish out of waterOne in alien circumstances
- drowningDeath by water inhalation
- in too deepUnable to extricate oneself
- incompetenceLack of required skill
anxiety · unpreparedness · thrown in · insecurity · helplessness · lost at sea · inexperience · misjudgment · sinking · confusion · swept away · deep end · floundering · swimming upstream · learning curve · steep learning · over one's head · overextension
out of one's depthin one's element
Ideally suited to surroundings
competent · up to the task · well-equipped · capable · qualified
out of one's depthat ease
Relaxed, not tense
comfortable · at home · relaxed · confident · self-assured
out of one's depthon solid ground
well-versed · expert · seasoned · experienced · knowledgeable