查了字典，关于stroke是名词时的意思：

stroke

2 of 3

noun

1

: the act of striking

especially  : a blow with a weapon or implement

 

2

: a single unbroken movement

especially  : one of a series of repeated or to-and-fro movements

 

3

a

: a controlled swing intended to hit a ball or shuttlecock

also  : a striking of the ball

b

: such a stroke charged to a player as a unit of scoring in golf

 

4

a

: a sudden action or process producing an impact

a stroke of lightning

 

b

: an unexpected result

a stroke of luck

 

the idea was a stroke of inspiration

 

a master stroke of diplomacy

 

 

5

: sudden impairment or loss of consciousness, sensation, and voluntary motion that is caused by rupture or obstruction (as by a clot) of a blood vessel supplying the brain, and is accompanied by permanent damage of brain tissue

NOTE: Symptoms of stroke include numbness or weakness on one side of the body or face, confusion, impaired speech or vision, loss of coordination or balance, trouble walking, or severe headache. 

  called also apoplexy,  brain attack, cerebrovascular accident

 compare ISCHEMIC STROKE, HEMORRHAGIC STROKE, TRANSIENT ISCHEMIC ATTACK

 

6

a

: one of a series of propelling beats or movements against a resisting medium

a stroke of the oar

 

b

: a rower who sets the pace for a crew

 

7

a

: a vigorous or energetic effort by which something is done, produced, or accomplished

a stroke of genius

 

a brilliant diplomatic stroke

 

b

: a delicate or clever touch in a narrative, description, or construction

 

8

: HEARTBEAT

 

9

: the movement in either direction of a mechanical part (such as a piston) having a reciprocating motion

also  : the distance of such movement

 

10

: the sound of a bell being struck

at the stroke of twelve

 

also  : the specific time indicated by or as if by such a sound

 

11

[stroke entry 1]  : an act of stroking or caressing

 

12

a

: a mark or dash made by a single movement of an implement

b

: one of the lines of a letter of the alphabet