Old French city stocking razors ultimately lacking blades (7)
I believe the answer is:
oarless
'lacking blades' is the definition.
(oars are blades for moving through water)
'old french city stocking razors ultimately' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'french city' becomes 'Arles' (city in France).
'stocking' indicates putting letters inside ('stock' can mean 'carry' or 'contain').
'ultimately' suggests the final letters.
The final letter of 'razors' is 's'.
'arles' placed around 's' is 'arless'.
'o'+'arless'='OARLESS'
(Other definitions for oarless that I've seen before include "unlikely to interfere?" , "Wanting Blades" , "Lacking a means of moving" , "like the coxswain" , "Without the means to row" .)